bl30: mailbox driver add unified error code [1/2]

PD#SH-18313

Problem:
Customer need add unified error code number on
mailbox driver for debug convenience

Solution:
Add unified error code number on mailbox driver
API

Verify:
A5_AV409

Change-Id: I04910679dbea062572290c8928717c8f06a80c7e
Signed-off-by: Yao Jie <jie.yao@amlogic.com>
16 files changed