git-show-ref --verify: Fail if called without a reference
git-show-ref --verify: Fail if called without a reference

builtin-show-ref.c (cmd_show_ref): Fail if called with --verify option but
without a reference.

Signed-off-by: Dmitry V. Levin <bca05f431daa7b310c1bddb44dde45fd267309e3@altlinux.org>
Signed-off-by: Junio C Hamano <dc50d1021234060e53ec42a77d526afa2fe07479@cox.net>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git