drm/msm: add input sanitization on debug dump debugfs

Add checks to debugfs input parameters in sde debug dump debugfs
entries.

Change-Id: Iea170b75c1eb9aa46366662d36e677cb3251830b
Signed-off-by: Lloyd Atkinson <latkinso@codeaurora.org>
Signed-off-by: Lakshmi Narayana Kalavala <lkalaval@codeaurora.org>