SoC Common: mailbox: optimize driver code size [1/3]

PD#SWPL-195147

Problem:
Need to optimize driver code size to avoid
size overflow

Solution:
Optimize mailbox driver code size

Verify:
Build Pass

Change-Id: Ifcb76d3bbbe350a8efc1d92fde6e5e053611064f
Signed-off-by: Yao Jie <jie.yao@amlogic.com>
1 file changed