drm/msm: add debugfs support to change ESD check interval

Add a debugfs entry to change ESD status check interval
from command line. This will help to debug any issues
related to ESD feature in runtime.

Change-Id: I4d056b049a0aa9b741588496d7885c52b444d858
Signed-off-by: Jayant Shekhar <jshekhar@codeaurora.org>