Update all usages of the MBOX API to the latest API changes (to be
squashed for bisectability).
Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>
This commit adds support for NXP board LPCXpresso55S69 for mbox.
- samples/drivers/mbox/ - mbox signaling mode
- samples/drivers/mbox_data/ - mbox data transfer mode
- tests/drivers/mbox/mbox_data/ - mbox test to verify functionality.
Signed-off-by: Tomas Galbicka <tomas.galbicka@nxp.com>