BUG/MEDIUM: Consistently use 'check' in process_chk

I am not entirely sure that this is a bug, but it seems
to me that it may cause a problem if there agent-check is
configured and there is some kind of error making a connection for it.

Signed-off-by: Simon Horman <horms@verge.net.au>
(cherry picked from commit ccaabcdfca23851af6fd83f4f3265284d283e2ab)
diff --git a/src/checks.c b/src/checks.c
index cba0018..f3b2b54 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -1541,7 +1541,7 @@
 		 * First, let's check whether there was an uncaught error,
 		 * which can happen on connect timeout or error.
 		 */
-		if (s->check.result == CHK_RES_UNKNOWN) {
+		if (check->result == CHK_RES_UNKNOWN) {
 			/* good connection is enough for pure TCP check */
 			if ((conn->flags & CO_FL_CONNECTED) && !check->type) {
 				if (check->use_ssl)