test: mkbp_fifo_depth_update
test: mkbp_fifo_depth_update

Verify updating mkbp_fifo queue depth.

BRANCH=none
BUG=b:244476858
TEST=./twister --clobber -s zephyr/test/drivers/drivers.mkbp -i

Signed-off-by: Aaron Massey <79529a820df71f45023239a3663736629646cc34@google.com>
Change-Id: I222122af86fb19ff8fcfd1ab05c00a1f3cbb5b4c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3873117
Reviewed-by: Jack Rosenthal <d3f605bef1867f59845d4ce6e4f83b8dc9e4e0ae@chromium.org>
Code-Coverage: Zoss <345cf107e82c70959d46f59d98bddc98ce458aff@prod.google.com>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec