drm/msm: Trigger unblank event during bootup

Touch driver needs DRM unblank event during bootup.
Currently the unblank event is triggered only during
suspend resume when userspace sets active property.
So, trigger unblank during boot up as well when
continuous splash is on. If continuous splash is off,
userspace specifically sets active which triggers
unblank event.

Change-Id: Ia5db9a1233b938b0cf1c670838e4cc4a41bd234f
Signed-off-by: Jayant Shekhar <jshekhar@codeaurora.org>