cros_workon_make: fix --scrub to scrub directories also

I was noticing wierdness in my build and pinned it down to having a
directory linger around after --scrub.

BUG=none
TEST=see below

$ mkdir foo
$ touch foo/bar
$ ec -- cros_workon_make --scrub kernel
WARNING : --scrub will destroy ALL FILES unknown to git!
Are you sure you want to do this? [y|N]y
Removing foo/

Change-Id: I3491cf9ff82f2a321482a239d92cf97a505af0bb
Note: ec is my alias for enter_chroot.sh
Reviewed-on: http://gerrit.chromium.org/gerrit/724
Tested-by: Mandeep Singh Baines <msb@chromium.org>
Reviewed-by: Chris Masone <cmasone@chromium.org>
1 file changed