CLEANUP: check: rename all occurrences of stconn "cs" to "sc"

The check struct had a "cs" field renamed to "sc", which also required
a tiny update to a few functions using it to distinguish a check from
a stream (log.c, payload.c, ssl_sample.c, tcp_sample.c, tcpcheck.c,
connection.c).

Function arguments and local variables called "cs" were renamed to "sc".
The presence of one "cs=" in the debugging traces was also turned to
"sc=" for consistency.
diff --git a/src/ssl_sample.c b/src/ssl_sample.c
index 6b5f794..35fcec3 100644
--- a/src/ssl_sample.c
+++ b/src/ssl_sample.c
@@ -1168,7 +1168,7 @@
 	struct connection *conn;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1205,7 +1205,7 @@
 	SSL *ssl;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1228,7 +1228,7 @@
 	SSL *ssl;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1262,7 +1262,7 @@
 	int sint;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1293,7 +1293,7 @@
 	SSL *ssl;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1325,7 +1325,7 @@
 	smp->data.type = SMP_T_STR;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1360,7 +1360,7 @@
 	smp->data.type = SMP_T_STR;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1393,7 +1393,7 @@
 	SSL *ssl;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1431,7 +1431,7 @@
 	smp->data.type = SMP_T_BIN;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1463,7 +1463,7 @@
 	SSL *ssl;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1500,7 +1500,7 @@
 	SSL *ssl;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1649,7 +1649,7 @@
 	struct ssl_sock_ctx *ctx;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1702,7 +1702,7 @@
 	const char *err_code_str;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;
@@ -1932,7 +1932,7 @@
 	SSL *ssl;
 
 	if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
-		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->cs) : NULL;
+		conn = (kw[4] == 'b') ? sc_conn(__objt_check(smp->sess->origin)->sc) : NULL;
 	else
 		conn = (kw[4] != 'b') ? objt_conn(smp->sess->origin) :
 			smp->strm ? sc_conn(smp->strm->scb) : NULL;