display: Clean up gralloc

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

Change-Id: If8ef543d236e5305bd5430f4f9c62c51b3a13787
diff --git a/libgralloc/memalloc.h b/libgralloc/memalloc.h
index 349078d..af509fb 100644
--- a/libgralloc/memalloc.h
+++ b/libgralloc/memalloc.h
@@ -31,7 +31,6 @@
 #define GRALLOC_MEMALLOC_H
 
 #include <stdlib.h>
-#include <utils/RefBase.h>
 
 namespace gralloc {
 
@@ -47,7 +46,7 @@
     int            allocType;
 };
 
-class IMemAlloc : public android::RefBase {
+class IMemAlloc {
 
     public:
     // Allocate buffer - fill in the alloc_data