receive-pack: plug memory leak in update()

Reported via Coverity.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/receive-pack.c

@@ -986,7 +986,8 @@ static const char *update(struct command *cmd, struct shallow_info *si)
 {
 	const char *name = cmd->ref_name;
 	struct strbuf namespaced_name_buf = STRBUF_INIT;
-	const char *namespaced_name, *ret;
+	static char *namespaced_name;
+	const char *ret;
 	struct object_id *old_oid = &cmd->old_oid;
 	struct object_id *new_oid = &cmd->new_oid;
 
@@ -997,6 +998,7 @@ static const char *update(struct command *cmd, struct shallow_info *si)
 	}
 
 	strbuf_addf(&namespaced_name_buf, "%s%s", get_git_namespace(), name);
+	free(namespaced_name);
 	namespaced_name = strbuf_detach(&namespaced_name_buf, NULL);
 
 	if (is_ref_checked_out(namespaced_name)) {