disp: msm: sde: save register write logs in dump

Changes are made to add register write logs to memory dump.
This can be extracted from crash dumps and used for analysis.

Change-Id: I02038f62ecee86a9c82a913c6ed24bdd18465686
Signed-off-by: Andhavarapu Karthik <kartkart@codeaurora.org>