MINOR: session: get rid of the now unused SESS_FL_ADDR_*_SET flags

That's similar to what was done for conn_streams and connections. The
flags were only set exactly when the relevant pointers were allocated,
so better test the pointer than the flag and stop setting the flag.
diff --git a/include/haproxy/session-t.h b/include/haproxy/session-t.h
index 1afb3c8..e7a9899 100644
--- a/include/haproxy/session-t.h
+++ b/include/haproxy/session-t.h
@@ -39,8 +39,6 @@
 enum {
 	SESS_FL_NONE          = 0x00000000, /* nothing */
 	SESS_FL_PREFER_LAST   = 0x00000001, /* NTML authent, we should reuse last conn */
-	SESS_FL_ADDR_FROM_SET = 0x00000002,
-	SESS_FL_ADDR_TO_SET   = 0x00000004,
 };
 
 /* max number of idle server connections kept attached to a session */
diff --git a/include/haproxy/session.h b/include/haproxy/session.h
index 695f5ed..ab4f28a 100644
--- a/include/haproxy/session.h
+++ b/include/haproxy/session.h
@@ -241,7 +241,7 @@
 {
 	struct connection *cli_conn = objt_conn(sess->origin);
 
-	if (sess->flags & SESS_FL_ADDR_FROM_SET)
+	if (sess->src)
 		return sess->src;
 	if (cli_conn && conn_get_src(cli_conn))
 		return conn_src(cli_conn);
@@ -256,7 +256,7 @@
 {
 	struct connection *cli_conn = objt_conn(sess->origin);
 
-	if (sess->flags & SESS_FL_ADDR_TO_SET)
+	if (sess->dst)
 		return sess->dst;
 	if (cli_conn && conn_get_dst(cli_conn))
 		return conn_dst(cli_conn);
@@ -274,7 +274,7 @@
 	struct connection *cli_conn = objt_conn(sess->origin);
 	const struct sockaddr_storage *src = NULL;
 
-	if (sess->flags & SESS_FL_ADDR_FROM_SET)
+	if (sess->src)
 		return 1;
 
 	if (cli_conn && conn_get_src(cli_conn))
@@ -285,7 +285,6 @@
 	if (!sockaddr_alloc(&sess->src, src, sizeof(*src)))
 		return 0;
 
-	sess->flags |= SESS_FL_ADDR_FROM_SET;
 	return 1;
 }
 
@@ -300,7 +299,7 @@
 	struct connection *cli_conn = objt_conn(sess->origin);
 	const struct sockaddr_storage *dst = NULL;
 
-	if (sess->flags & SESS_FL_ADDR_TO_SET)
+	if (sess->dst)
 		return 1;
 
 	if (cli_conn && conn_get_dst(cli_conn))
@@ -311,7 +310,6 @@
 	if (!sockaddr_alloc(&sess->dst, dst, sizeof(*dst)))
 		return 0;
 
-	sess->flags |= SESS_FL_ADDR_TO_SET;
 	return 1;
 }
 
diff --git a/src/connection.c b/src/connection.c
index e3e1bc8..e92089e 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -885,7 +885,6 @@
 		((struct sockaddr_in *)sess->dst)->sin_family        = AF_INET;
 		((struct sockaddr_in *)sess->dst)->sin_addr.s_addr   = htonl(dst3);
 		((struct sockaddr_in *)sess->dst)->sin_port          = htons(dport);
-		sess->flags |= SESS_FL_ADDR_FROM_SET | SESS_FL_ADDR_TO_SET;
 	}
 	else if (memcmp(line, "TCP6 ", 5) == 0) {
 		u32 sport, dport;
@@ -949,7 +948,6 @@
 		((struct sockaddr_in6 *)sess->dst)->sin6_family        = AF_INET6;
 		memcpy(&((struct sockaddr_in6 *)sess->dst)->sin6_addr, &dst3, sizeof(struct in6_addr));
 		((struct sockaddr_in6 *)sess->dst)->sin6_port          = htons(dport);
-		sess->flags |= SESS_FL_ADDR_FROM_SET | SESS_FL_ADDR_TO_SET;
 	}
 	else if (memcmp(line, "UNKNOWN\r\n", 9) == 0) {
 		/* This can be a UNIX socket forwarded by an haproxy upstream */
@@ -997,7 +995,6 @@
 			((struct sockaddr_in *)sess->dst)->sin_family = AF_INET;
 			((struct sockaddr_in *)sess->dst)->sin_addr.s_addr = hdr_v2->addr.ip4.dst_addr;
 			((struct sockaddr_in *)sess->dst)->sin_port = hdr_v2->addr.ip4.dst_port;
-			sess->flags |= SESS_FL_ADDR_FROM_SET | SESS_FL_ADDR_TO_SET;
 			tlv_offset = PP2_HEADER_LEN + PP2_ADDR_LEN_INET;
 			break;
 		case 0x21:  /* TCPv6 */
@@ -1013,7 +1010,6 @@
 			((struct sockaddr_in6 *)sess->dst)->sin6_family = AF_INET6;
 			memcpy(&((struct sockaddr_in6 *)sess->dst)->sin6_addr, hdr_v2->addr.ip6.dst_addr, 16);
 			((struct sockaddr_in6 *)sess->dst)->sin6_port = hdr_v2->addr.ip6.dst_port;
-			sess->flags |= SESS_FL_ADDR_FROM_SET | SESS_FL_ADDR_TO_SET;
 			tlv_offset = PP2_HEADER_LEN + PP2_ADDR_LEN_INET6;
 			break;
 		}
@@ -1372,8 +1368,6 @@
 		((struct sockaddr_in *)sess->dst)->sin_family = AF_INET;
 		((struct sockaddr_in *)sess->dst)->sin_addr.s_addr = hdr_ip4->ip_dst.s_addr;
 		((struct sockaddr_in *)sess->dst)->sin_port = hdr_tcp->dest;
-
-		sess->flags |= SESS_FL_ADDR_FROM_SET | SESS_FL_ADDR_TO_SET;
 	}
 	else if (ip_ver == 6) {
 		struct ip6_hdr *hdr_ip6;
@@ -1405,8 +1399,6 @@
 		((struct sockaddr_in6 *)sess->dst)->sin6_family = AF_INET6;
 		((struct sockaddr_in6 *)sess->dst)->sin6_addr = hdr_ip6->ip6_dst;
 		((struct sockaddr_in6 *)sess->dst)->sin6_port = hdr_tcp->dest;
-
-		sess->flags |= SESS_FL_ADDR_FROM_SET | SESS_FL_ADDR_TO_SET;
 	}
 	else {
 		/* The protocol does not match something known (IPv4/IPv6) */