LWIS: Add lock to protect register accessing

There is no lock when we accessing the register. Add spinlock protection
to prevent access register at the same time.

Bug: 237180008
Test: GCA, CTS
Signed-off-by: Holmes Chou <holmeschou@google.com>
Change-Id: I1dd9d850d37897cbd8ba8c983a01a21e295ee8c8
6 files changed