Audit rev-parse users.

Make sure that we say --verify when we want to get a single SHA1
name.  Also when we say --verify, --revs-only is redundant.

Signed-off-by: Junio C Hamano <junkio@cox.net>

git-reset-script

@@ -1,7 +1,7 @@
 #!/bin/sh
 . git-sh-setup-script || die "Not a git archive"
-rev=$(git-rev-parse --revs-only --verify --default HEAD "$@") || exit
-rev=$(git-rev-parse --revs-only --verify $rev^0) || exit
+rev=$(git-rev-parse --verify --default HEAD "$@") || exit
+rev=$(git-rev-parse --verify $rev^0) || exit
 git-read-tree --reset "$rev" && {
 	if orig=$(git-rev-parse --verify HEAD 2>/dev/null)
 	then