If the revision number starts with r, drop it. It will get added back
later and we don't want to use it twice.

llvm-svn: 273099
diff --git a/llvm/utils/release/merge.sh b/llvm/utils/release/merge.sh
index b489322..e241dcd 100755
--- a/llvm/utils/release/merge.sh
+++ b/llvm/utils/release/merge.sh
@@ -31,7 +31,7 @@
     case $1 in
         -rev | --rev | -r )
             shift
-            rev=$1
+            rev=${$1#r}
             ;;
         -proj | --proj | -project | --project | -p )
             shift