display: Clean up gralloc

* Remove pmem and ashmem implementations
* Remove usage of RefBase
* Reduce log verbosity

Change-Id: If8ef543d236e5305bd5430f4f9c62c51b3a13787
diff --git a/libcopybit/copybit.cpp b/libcopybit/copybit.cpp
index 886d12b..b8118a0 100644
--- a/libcopybit/copybit.cpp
+++ b/libcopybit/copybit.cpp
@@ -411,8 +411,7 @@
         }
 
         if(src->format ==  HAL_PIXEL_FORMAT_YV12) {
-            int usage = GRALLOC_USAGE_PRIVATE_ADSP_HEAP |
-                GRALLOC_USAGE_PRIVATE_MM_HEAP;
+            int usage = GRALLOC_USAGE_PRIVATE_MM_HEAP;
             if (0 == alloc_buffer(&yv12_handle,src->w,src->h,
                                   src->format, usage)){
                 if(0 == convertYV12toYCrCb420SP(src,yv12_handle)){