CLEANUP: remove trashlen

trashlen is a copy of global.tune.bufsize, so let's stop using it as
a duplicate, fall back to the original bufsize, it's less confusing
this way.
diff --git a/src/checks.c b/src/checks.c
index 326ffde..0c385ca 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -238,7 +238,7 @@
 
 		int health, rise, fall, state;
 
-		chunk_init(&msg, trash, trashlen);
+		chunk_init(&msg, trash, global.tune.bufsize);
 
 		/* FIXME begin: calculate local version of the health/rise/fall/state */
 		health = s->health;
@@ -418,7 +418,7 @@
 		 */
 		xferred = redistribute_pending(s);
 
-		chunk_init(&msg, trash, trashlen);
+		chunk_init(&msg, trash, global.tune.bufsize);
 
 		if (s->state & SRV_MAINTAIN) {
 			chunk_printf(&msg,
@@ -510,7 +510,7 @@
 		 */
 		xferred = check_for_pending(s);
 
-		chunk_init(&msg, trash, trashlen);
+		chunk_init(&msg, trash, global.tune.bufsize);
 
 		if (old_state & SRV_MAINTAIN) {
 			chunk_printf(&msg,
@@ -557,7 +557,7 @@
 	 */
 	xferred = redistribute_pending(s);
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 
 	chunk_printf(&msg,
 		"Load-balancing on %sServer %s/%s is disabled",
@@ -594,7 +594,7 @@
 	 */
 	xferred = check_for_pending(s);
 
-	chunk_init(&msg, trash, trashlen);
+	chunk_init(&msg, trash, global.tune.bufsize);
 
 	chunk_printf(&msg,
 		"Load-balancing on %sServer %s/%s is enabled again",