hwc: Add support for FB scaling and cloning

Patch contains following features
1)Large frame buffer support:
     Transformation matrix for LCD and HDMI added
     to ensure correct composition and renderring
     of all UI layers
     Added support for overlay distrubution based
     on FB size and target display
2)Default HDMI display support
     Support for default HDMI display selection.
     Added HDMI best mode selection on HPD

Rebased from p-ics-mr1:
96ad001 hwc: Add support for FB scaling and cloning

Change-Id: Ia6f06d5e149656c4d79ac2d3983211a253bb3969
Signed-off-by: Lajos Molnar <molnar@ti.com>
Signed-off-by: Muralidhar Dixit <murali.dixit@ti.com>
Signed-off-by: Dandawate Saket <dsaket@ti.com>