gpio_defines: make header visible to chameleon

Move this to include/ so chameleon can use it too.

BUG=b:174754428
TEST=compiles

Change-Id: I8898a7e2beb5c30c0577fe0fd36d69fe631d0624
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/zephyr-chrome/+/2570998
Tested-by: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-by: Paul Fagerburg <pfagerburg@chromium.org>
3 files changed