BUG/MINOR: config: fix improper check for failed memory alloc in ACL parser

The wrong variable is checked after a calloc() so a memory shortage would
result in a segfault while loading the config instead of a clean error.

This fix may be backported to 1.4 and 1.3 which are both affected.

Reported-by: Dinko Korunic <dkorunic@reflected.net>
diff --git a/src/acl.c b/src/acl.c
index cba89ab..753f109 100644
--- a/src/acl.c
+++ b/src/acl.c
@@ -1840,7 +1840,7 @@
 
 		if (!cur_suite) {
 			cur_suite = (struct acl_term_suite *)calloc(1, sizeof(*cur_suite));
-			if (cur_term == NULL) {
+			if (cur_suite == NULL) {
 				memprintf(err, "out of memory when parsing condition");
 				goto out_free_term;
 			}