BUILD: haproxy: fix build error when RLIMIT_AS is not set

As reported in issue #724, openbsd fails to build in haproxy.c
due to a faulty comma in the middle of a warning message. This code
is only compiled when RLIMIT_AS is not defined, which seems to be
rare these days.

This may be backported to older versions as the problem was likely
introduced when strict limits were added.
diff --git a/src/haproxy.c b/src/haproxy.c
index e733d45..7537d93 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -3204,7 +3204,7 @@
 					exit(1);
 			}
 			else
-				ha_warning("[%s.main()] Cannot fix MEM limit to %d megs.",
+				ha_warning("[%s.main()] Cannot fix MEM limit to %d megs."
 					   "This will fail in >= v2.3\n",
 					   argv[0], global.rlimit_memmax);
 		}