gralloc: Deprecate old stuff.

1. Reclaim some old gralloc flags.
2. System heap allocation happens by default.
3. Remove some unused private flags.
4. Add heapid member to alloc_data to better line up with ion
   header
5. Remove check for MDSS_TARGET

Change-Id: I37be0a2fcd5fd4a14bb9ca235fcae41f6f3ec19e
diff --git a/libhwcomposer/hwc_copybit.cpp b/libhwcomposer/hwc_copybit.cpp
index 744195f..d4bcc88 100644
--- a/libhwcomposer/hwc_copybit.cpp
+++ b/libhwcomposer/hwc_copybit.cpp
@@ -979,7 +979,7 @@
 
        ALOGD("%s:%d::tmp_w = %d,tmp_h = %d",__FUNCTION__,__LINE__,tmp_w,tmp_h);
 
-       int usage = GRALLOC_USAGE_PRIVATE_IOMMU_HEAP;
+       int usage = 0;
        int format = fbHandle->format;
 
        // We do not want copybit to generate alpha values from nothing
@@ -1145,8 +1145,7 @@
     for (int i = 0; i < NUM_RENDER_BUFFERS; i++) {
         if (mRenderBuffer[i] == NULL) {
             ret = alloc_buffer(&mRenderBuffer[i],
-                               w, h, f,
-                               GRALLOC_USAGE_PRIVATE_IOMMU_HEAP);
+                               w, h, f, 0);
         }
         if(ret < 0) {
             freeRenderBuffers();