Sweetberry specifies UART pins as GPIOs, however
this is not necessary for uart use. Let's remove these.
UART4 is also dup'd with sweetberry's signal gpios, which
is fixed with this CL.
BUG=chromium:608039
TEST=boots
BRANCH=None
Change-Id: I81ee2351c0191ff5ec3d5fad37fe10866bf1ad32
Signed-off-by: Nick Sanders <nsanders@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/380439
Reviewed-by: Bill Richardson <wfrichar@chromium.org>