soc: qcom: spss_utils: fix spu uefi apps saved cmac on SSR

keep and restore the spu apps saved cmac.
The cmac are written by spss uefi driver on boot.
They are overwritten by PIL when reload spu on SSR.

Change-Id: Ia93942b425c7ad7c83c7b032f7bf6bbbf60de435
Signed-off-by: Amir Samuelov <amirs@codeaurora.org>