Merge upstream changes from Marlin 2.1.1

buildroot/share/git/mfrb

@@ -2,7 +2,7 @@
 #
 # mfrb
 #
-# Do "git rebase -i" against the "target" branch (bugfix-1.1.x, bugfix-2.0.x, dev-2.1.x, or master)
+# Do "git rebase -i" against the repo's "target" branch
 #
 
 MFINFO=$(mfinfo "$@") || exit 1
@@ -21,7 +21,7 @@ while [ $IND -lt ${#INFO[@]} ]; do
   let IND+=1
 done
 
-[[ $USAGE == 1 ]] && { echo "usage: `basename $0` [1|2|3]" 1>&2 ; exit 1 ; }
+[[ $USAGE == 1 ]] && { echo "usage: `basename $0` [1|2]" 1>&2 ; exit 1 ; }
 
 [[ $QUICK ]] || git fetch upstream
 git rebase upstream/$TARG && git rebase -i upstream/$TARG