[tools] Backport validator: handle unmaintained

When the script was created there were only stable/* branches, but now
there are unmaintained/* branches as well, where the validator fails
when looking for hashes only on stable/* branches even if the given
hash is already on unmtaintained/* branch. This patch matches now both
stable/* and unmaintained/* branches.

Change-Id: I08fcc63ab0fbe5af1be70d5fde5af98bf006101c
(cherry picked from commit e2697de)
(cherry picked from commit 602e683)
(cherry picked from commit 56e73cc)
(cherry picked from commit f53824f)
(cherry picked from commit f43ceef)
(cherry picked from commit 7b7bac3)
(cherry picked from commit 7cef0d3)

Author: Elod Illes

tools/check-cherry-picks.sh

@@ -1,7 +1,8 @@
 #!/bin/sh
 #
 # A tool to check the cherry-pick hashes from the current git commit message
-# to verify that they're all on either master or stable/ branches
+# to verify that they're all on either master, stable/ or unmaintained/
+# branches
 #
 
 commit_hash=""
@@ -18,17 +19,17 @@ hashes=$(git show --format='%b' --quiet $commit_hash | sed -nr 's/^.cherry picke
 checked=0
 branches+=""
 for hash in $hashes; do
-    branch=$(git branch -a --contains "$hash" 2>/dev/null| grep -oE '(master|stable/[a-z0-9.]+)')
+    branch=$(git branch -a --contains "$hash" 2>/dev/null| grep -oE '(master|stable/[a-z0-9.]+|unmaintained/[a-z0-9.]+)')
     if [ $? -ne 0 ]; then
-        echo "Cherry pick hash $hash not on any master or stable branches"
+        echo "Cherry pick hash $hash not on any master, stable or unmaintained branches"
         exit 1
     fi
     branches+=" $branch"
     checked=$(($checked + 1))
 done
 
 if [ $checked -eq 0 ]; then
-    if ! grep -q '^defaultbranch=stable/' .gitreview; then
+    if ! grep -qE '^defaultbranch=(stable|unmaintained)/' .gitreview; then
         echo "Checked $checked cherry-pick hashes: OK"
         exit 0
     else