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
Revert "Revert "libhwcomposer: Don't count video layers marked for SKIP""

This reverts commit 5b9ee9522eff9f43eb13692e2d15f8d500b680a2.