gralloc: plane support

patch introduces API between hwcomposer and gralloc, hwcomposer can
reserve an overlay plane to be used by a particular layer in prepare
hook, drmModeSetPlane for each plane gets called later when post()
gets called by the eglSwapBuffers (from hwcomposer set), this can be
later changed to use atomic modesetting code and drm properties to
make one 'atomic flip' for graphics + planes.

Change-Id: I3b7d179b285e43eb19fdc3b4c7ce093f3ba6aade
Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
4 files changed