./g: don't exit early on ./g checkout -f

Change-Id: I33f54c365bce64ccccfeb1c58fc8e4faddb7ad77
Reviewed-on: https://gerrit.libreoffice.org/56822Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>
Tested-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>

g

@@ -201,7 +201,7 @@ do_checkout()
     git checkout "$@" || return $?
     for cmd in "$@" ; do
         if [ "$cmd" = "-f" ]; then
-            return 0
+            continue
         elif [ "$cmd" = "-b" ] ; then
             create_branch=1
         elif [ "$create_branch" = "1" ] ; then