scripts/getver.sh: silence rev-list errors

Shallow copies are quite common on CI platforms nowadays, making REBOOT
tag unavailable, thus producing following confusing errors in the build
logs:

 fatal: Invalid revision range ee53a240ac902dc83209008a2671e7fdcf55957a..HEAD
 fatal: Invalid revision range ee53a240ac902dc83209008a2671e7fdcf55957a..0493d57e04774d47921a7d2014b567455d5dc16b

Signed-off-by: Petr Štetiar <[email protected]>

scripts/getver.sh

@@ -20,18 +20,18 @@ try_git() {
 	case "$GET_REV" in
 	r*)
 		GET_REV="$(echo $GET_REV | tr -d 'r')"
-		BASE_REV="$(git rev-list ${REBOOT}..HEAD | wc -l | awk '{print $1}')"
+		BASE_REV="$(git rev-list ${REBOOT}..HEAD 2>/dev/null | wc -l | awk '{print $1}')"
 		REV="$(git rev-parse HEAD~$((BASE_REV - GET_REV)))"
 		;;
 	*)
 		BRANCH="$(git rev-parse --abbrev-ref HEAD)"
 		ORIGIN="$(git rev-parse --verify --symbolic-full-name ${BRANCH}@{u} 2>/dev/null)"
 		[ -n "$ORIGIN" ] || ORIGIN="$(git rev-parse --verify --symbolic-full-name master@{u} 2>/dev/null)"
-		REV="$(git rev-list ${REBOOT}..$GET_REV | wc -l | awk '{print $1}')"
+		REV="$(git rev-list ${REBOOT}..$GET_REV 2>/dev/null | wc -l | awk '{print $1}')"
 
 		if [ -n "$ORIGIN" ]; then
 			UPSTREAM_BASE="$(git merge-base $GET_REV $ORIGIN)"
-			UPSTREAM_REV="$(git rev-list ${REBOOT}..$UPSTREAM_BASE | wc -l | awk '{print $1}')"
+			UPSTREAM_REV="$(git rev-list ${REBOOT}..$UPSTREAM_BASE 2>/dev/null | wc -l | awk '{print $1}')"
 		else
 			UPSTREAM_REV=0
 		fi