Combined Cherry-Pick (display: and Revert "hwc...")

display: Use actual kernel headers for all builds

 * Kill all device headers.

Change-Id: I1add22c0bc33942bc8f89dbb37333bf08d49bf72

Revert "hwc: Configure pipe for FB even if we exceed max layers"

This commit seems to be causing cached frame redraw on d2vzw in
various applications. (moonreader / appygeek / falcon pro / facebook)
This reverts commit 68f1fcb822d49bd5362c4627beae74631fd40375.