board/chromebook: use global-patch-dir for kernel patch

We're going to add hashes soon, so we'll need to have that directory
populated with hash files, and it would then be a bit confusing to not
have the patch file in the patches directory...

Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
Cc: Alex Suykov <alex.suykov@gmail.com>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>
(cherry picked from commit 552a8cec8cb1a9a66591d075992957ad32547528)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
3 files changed