VC4 GPU Build

After 'repo sync' step of https://github.com/peyo-hd/local_manifests/tree/marshmallow, Do 'git checkout vc4' on following sources.

• kernel/rpi
• device/brcm/rpi2

Apply following patch under frameworks/base

To prevent logcat flood by mouse event

 core/java/android/view/GestureDetector.java
 @@ line 490 @@ public class GestureDetector {
     public boolean onTouchEvent(MotionEvent ev) {
 +        switch(ev.getAction() & MotionEvent.ACTION_MASK) {
 +        case MotionEvent.ACTION_HOVER_MOVE:
 +        case MotionEvent.ACTION_HOVER_ENTER:
 +        case MotionEvent.ACTION_HOVER_EXIT:
 +        case MotionEvent.ACTION_BUTTON_PRESS:
 +        case MotionEvent.ACTION_BUTTON_RELEASE:
 +        case MotionEvent.ACTION_SCROLL:
 +            return false;
 +        }
          if (mInputEventConsistencyVerifier != null) {

Then follow README of https://github.com/peyo-hd/device_brcm_rpi2/tree/vc4

For vc4 original work of Eric Anholt, refer to http://dri.freedesktop.org/wiki/VC4 And his github : https://github.com/anholt