gralloc1: Deprecate usage flags for internal/external only

Deprecate internal/external only usage flags that are no
longer needed.

Change-Id: Id4fc6d780ac98327befbd723b9e48356b834fb7f
CRs-Fixed: 2070081
diff --git a/libgralloc1/gralloc_priv.h b/libgralloc1/gralloc_priv.h
index 1839d2f..246ba90 100644
--- a/libgralloc1/gralloc_priv.h
+++ b/libgralloc1/gralloc_priv.h
@@ -63,11 +63,11 @@
 /* This flag is used for SECURE display usecase */
 #define GRALLOC1_CONSUMER_USAGE_PRIVATE_SECURE_DISPLAY 0x00800000
 
-/* Buffer content should be displayed on a primary display only */
-#define GRALLOC1_CONSUMER_USAGE_PRIVATE_INTERNAL_ONLY  0x04000000
+/* Unused flag */
+#define GRALLOC1_USAGE_PRIVATE_UNUSED1  0x04000000
 
-/* Buffer content should be displayed on an external display only */
-#define GRALLOC1_CONSUMER_USAGE_PRIVATE_EXTERNAL_ONLY  0x08000000
+/* Unused flag */
+#define GRALLOC1_USAGE_PRIVATE_UNUSED2  0x08000000
 
 
 /* Legacy gralloc0.x definitions */