hwc: Add target specific checks in hwcomposer

* Mdss driver supports DMA-Multiplexing on wb interface
for certain targets. Add overlay get function to query
this info during pipe allocation for wb.

* UI Scaling on external is not supported on certain
targets due to the lack of availability of pipes with
scalars. Add overlay get function to query this info
to disable action-safe calcs, DRC and others which
require downscaling.

Change-Id: I1726caa4634f72d781561e797078648524ea2eef
diff --git a/libhwcomposer/hwc.cpp b/libhwcomposer/hwc.cpp
index cbc42b2..aa7a187 100644
--- a/libhwcomposer/hwc.cpp
+++ b/libhwcomposer/hwc.cpp
@@ -146,7 +146,7 @@
 
                     if (UNLIKELY(isYuvBuffer(hnd)) && canUseRotator(ctx,i) &&
                         (layer->transform & HWC_TRANSFORM_ROT_90)) {
-                        if(not qdutils::MDPVersion::getInstance().is8x26()) {
+                        if(not ctx->mOverlay->isDMAMultiplexingSupported()) {
                             if(ctx->mOverlay->isPipeTypeAttached(
                                              overlay::utils::OV_MDP_PIPE_DMA))
                                 ctx->isPaddingRound = true;