display: Don't enable pixel repeat for YUV buffers

 * This can cause horrible things to happen on msm8660 like clock rates
   going to a zillion hz, hard lockups, artifacts, and the smell of
   fresh ozone in the air. Don't do it.

Change-Id: Ic3b8541fc149c593e46ca5ed0c1ee14cab6af71a

libhwcomposer/hwc_mdpcomp.cpp

@@ -191,7 +191,8 @@ int MDPComp::prepare(hwc_context_t *ctx, hwc_layer_1_t *layer,
         if(isYuvBuffer(hnd))
             setVidInfo(layer, mdpFlags);
 
-        ovutils::setMdpFlags(mdpFlags,ovutils::OV_MDP_BACKEND_COMPOSITION);
+        if (!isYuvBuffer(hnd))
+            ovutils::setMdpFlags(mdpFlags,ovutils::OV_MDP_BACKEND_COMPOSITION);
 
         if(layer->blending == HWC_BLENDING_PREMULT) {
             ovutils::setMdpFlags(mdpFlags,