Fix pushing to a pattern with no dst

Refspecs with no colons are left with no dst value, because they are
interepreted differently for fetch and push. For push, they mean to
reuse the src side. Fix this for patterns.
Signed-off-by: NDaniel Barkalow <barkalow@iabervon.org>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

remote.c

@@ -536,10 +536,11 @@ int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 		}
 
 		if (pat) {
-			dst_name = xmalloc(strlen(pat->dst) +
+			const char *dst_side = pat->dst ? pat->dst : pat->src;
+			dst_name = xmalloc(strlen(dst_side) +
 					   strlen(src->name) -
 					   strlen(pat->src) + 2);
-			strcpy(dst_name, pat->dst);
+			strcpy(dst_name, dst_side);
 			strcat(dst_name, src->name + strlen(pat->src));
 		} else
 			dst_name = xstrdup(src->name);