drm/msm/sde: output black frame during resume operation

This patch provides a module parameter to control whether each
plane outputs the previously configured content or a black frame
during the resume operation. The default is set to output a
black frame.

CRs-Fixed: 2019307
Change-Id: I48c1a8edfa1e85252a070bda51228ef67dea041c
Signed-off-by: Clarence Ip <cip@codeaurora.org>