gralloc: Use PROTECTED flag for L1 allocations

This is in keeping with the gralloc spec.

Change-Id: Id796a55e2ea51d3abdf9274140dc0404a42e1cab
CRs-fixed: 999994
diff --git a/libgralloc/alloc_controller.cpp b/libgralloc/alloc_controller.cpp
index 2eb1adc..45901ee 100644
--- a/libgralloc/alloc_controller.cpp
+++ b/libgralloc/alloc_controller.cpp
@@ -446,23 +446,16 @@
     data.allocType = 0;
 
     if(usage & GRALLOC_USAGE_PROTECTED) {
-        if (usage & GRALLOC_USAGE_PRIVATE_MM_HEAP) {
-            if (usage & GRALLOC_USAGE_PRIVATE_SECURE_DISPLAY) {
-                ionHeapId = ION_HEAP(SD_HEAP_ID);
-                /*
-                 * There is currently no flag in ION for Secure Display
-                 * VM. Please add it to the define once available.
-                */
-                ionFlags |= ION_SD_FLAGS;
-            } else {
-                ionHeapId = ION_HEAP(CP_HEAP_ID);
-                ionFlags |= ION_CP_FLAGS;
-            }
+        if (usage & GRALLOC_USAGE_PRIVATE_SECURE_DISPLAY) {
+            ionHeapId = ION_HEAP(SD_HEAP_ID);
+            /*
+             * There is currently no flag in ION for Secure Display
+             * VM. Please add it to the define once available.
+             */
+            ionFlags |= ION_SD_FLAGS;
         } else {
-            // for targets/OEMs which do not need HW level protection
-            // do not set ion secure flag & MM heap. Fallback to system heap.
-            ionHeapId |= ION_HEAP(ION_SYSTEM_HEAP_ID);
-            data.allocType |= private_handle_t::PRIV_FLAGS_PROTECTED_BUFFER;
+            ionHeapId = ION_HEAP(CP_HEAP_ID);
+            ionFlags |= ION_CP_FLAGS;
         }
     } else if(usage & GRALLOC_USAGE_PRIVATE_MM_HEAP) {
         //MM Heap is exclusively a secure heap.