zephyr: drivers: add TCPCI messages related tests
zephyr: drivers: add TCPCI messages related tests

This patch adds unit tests for driver/tcpm/tcpci.c functions that are
related to sending and receiving SOP messages.

BUG=b:184857030
BRANCH=none
TEST=make configure --test zephyr/test/drivers

Signed-off-by: Tomasz Michalec <a547db31280d14f095c760a23a7523d0b1e55fe6@semihalf.com>
Change-Id: I5f839c9c1c5e0c2f37c7ef9c6ba91ab06b1de21d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3220337
Reviewed-by: Sam Hurst <500b4cddcd66abe3fe333e92c4c95d7f41e62e4e@google.com>
Tested-by: Tomasz Michalec <c064a6042954d4ba0805003dc021b76413ff1548@google.com>
Commit-Queue: Tomasz Michalec <c064a6042954d4ba0805003dc021b76413ff1548@google.com>

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