msm: mdss: Add support for checking panel status through register read

ESD feature may need to check the status of the panel by reading specific
panel register depending on the panel. Add support for ESD status check
through status register read and to configure the method used for checking
panel status through panel dtsi entry.

CRs-Fixed: 660805
Change-Id: I13b11362722eb2ad379162944eafff04ec01d1cb
Signed-off-by: Shivaraj Shetty <shivaraj@codeaurora.org>