Use the modern syntax of git-diff-files in t2002-checkout-cache-u.sh
Use the modern syntax of git-diff-files in t2002-checkout-cache-u.sh

As a nice side effect it also fixes t2002-checkout-cache-u.sh on FreeBSD 4,
/bin/sh of which has problems interpreting "! command" construction.

Signed-off-by: Alex Riesen <053ce55f4869b7f450d1d77b8f162c6f2bb9e137@gmail.com>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git