libgralloc: Add support to use CAMERA_HEAP

- Adds flag GRALLOC_USAGE_PRIVATE_CAMERA_HEAP to use the dedicated
  CAMERA_HEAP
- Remove GRALLOC_USAGE_PRIVATE_CP_BUFFER which is not used anymore

Change-Id: Iefea88d9a67d2fa0ca74492f508e1d5508d08983

libgralloc/alloc_controller.cpp

@@ -217,6 +217,9 @@ int IonController::allocate(alloc_data& data, int usage)
         }
     }
 
+    if(usage & GRALLOC_USAGE_PRIVATE_CAMERA_HEAP)
+        ionFlags |= ION_HEAP(ION_CAMERA_HEAP_ID);
+
     if(usage & GRALLOC_USAGE_PRIVATE_ADSP_HEAP)
         ionFlags |= ION_HEAP(ION_ADSP_HEAP_ID);