BUG/MAJOR: fix a segfault on option http_proxy and url_ip acl

url2sa() mistakenly uses "addr" as a reference. This causes a segfault when
option http_proxy or url_ip are used.

This bug was introduced in haproxy 1.5 and doesn't need to be backported.
diff --git a/src/standard.c b/src/standard.c
index 287931a..76031e9 100644
--- a/src/standard.c
+++ b/src/standard.c
@@ -906,12 +906,12 @@
 			 * be warned this can slow down global daemon performances
 			 * while handling lagging dns responses.
 			 */
-			ret = url2ipv4(curr, &((struct sockaddr_in *)&addr)->sin_addr);
+			ret = url2ipv4(curr, &((struct sockaddr_in *)addr)->sin_addr);
 			if (!ret)
 				return -1;
 			curr += ret;
 			((struct sockaddr_in *)addr)->sin_port = (*curr == ':') ? str2uic(++curr) : 80;
-			((struct sockaddr_in *)addr)->sin_port = htons(((struct sockaddr_in *)&addr)->sin_port);
+			((struct sockaddr_in *)addr)->sin_port = htons(((struct sockaddr_in *)addr)->sin_port);
 		}
 		return 0;
 	}