disp: msm: update debug dump for ltm block

Local tone mapping hardware block has defined test points for debug bus.
Change updates the missing test points and enables dumping of the
registers in case of DPU hang.

Change-Id: I5bb5419255e84427c0a1393f8e9322b981eea084
Signed-off-by: Gopikrishnaiah Anandan <agopik@codeaurora.org>