drm/msm/sde: decouple early mapping of display splash buffer

Currently in display driver splash buffer is allocated after resource
manager is initialized. LUT dma block should be initialized before the
resource manager init so that dspp/sspp blocks can use the AXI path for
lut programming.

Change-Id: I1ecb69379988148068daf68adab1f227050c9879
Signed-off-by: Gopikrishnaiah Anandan <agopik@codeaurora.org>
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>