scripts: hide double git reference check error

When checking a git reference which does not exist, a git error
with the long git-branch usage is printed:

% scripts/check-git-log.sh '-1 3780cbd'
error: malformed object name 2de9f8551ff9
usage: git branch ...
  [a lot of lines]
Wrong 'Fixes' reference:
  Fixes: 2de9f8551ff9 ("ethdev: fix documentation for queue start/stop")

The error from the script is sufficient so the git error can be hidden.

Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>

diff --git a/scripts/check-git-log.sh b/scripts/check-git-log.sh
index e416aea..6137098 100755 (executable)
--- a/scripts/check-git-log.sh
+++ b/scripts/check-git-log.sh
@@ -180,7 +180,7 @@ IFS='
 fixtags=$(echo "$tags" | grep '^Fixes: ')
 bad=$(for fixtag in $fixtags ; do
        hash=$(echo "$fixtag" | sed 's,^Fixes: \([0-9a-f]*\).*,\1,')
-       if git branch --contains $hash | grep -q '^\*' ; then
+       if git branch --contains $hash 2>&- | grep -q '^\*' ; then
                good="Fixes: $hash "$(git log --format='("%s")' -1 $hash 2>&-)
        else
                good="reference not in current branch"