Update git helper scripts

buildroot/share/git/mfnew

@@ -5,15 +5,29 @@
 # Create a new branch from the default target with the given name
 #
 
-[[ $# < 2 ]] || { echo "Usage: `basename $0` [branch]" 1>&2 ; exit 1; }
+usage() {
+  echo "Usage: `basename $0` [1|2] [name]" 1>&2
+}
 
-MFINFO=$(mfinfo) || exit 1
+[[ $# < 3 ]] || { usage ; exit 1 ; }
+
+MFINFO=$(mfinfo "$@") || exit 1
 IFS=' ' read -a INFO <<< "$MFINFO"
 TARG=${INFO[3]}
+BRANCH=pr_for_$TARG-$(date +"%G-%m-%d_%H.%M.%S")
 
+# BRANCH can be given as the last argument
 case "$#" in
-  0 ) BRANCH=pr_for_$TARG-$(date +"%G-%m-%d_%H.%M.%S") ;;
-  1 ) BRANCH=$1 ;;
+  1 ) case "$1" in
+        1|2) ;;
+        *) BRANCH=$1 ;;
+      esac
+      ;;
+  2 ) case "$1" in
+        1|2) BRANCH=$2 ;;
+        *) usage ; exit 1 ;;
+      esac
+      ;;
 esac
 
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