Fix producer usage in virtual camera

Per documentation the HAL should add its own usage flag on top of the
ones provided by the hal stream config.

Test: Camera CTS, VirtualCamera CTS
Flag: EXEMPT bugfix
Change-Id: I84e268929ee9afb94ac9fcf041cf6b3ba2419c0d
diff --git a/services/camera/virtualcamera/VirtualCameraSession.cc b/services/camera/virtualcamera/VirtualCameraSession.cc
index e1815c7..d074826 100644
--- a/services/camera/virtualcamera/VirtualCameraSession.cc
+++ b/services/camera/virtualcamera/VirtualCameraSession.cc
@@ -191,7 +191,11 @@
   }
   halStream.overrideDataSpace = stream.dataSpace;
 
-  halStream.producerUsage = BufferUsage::GPU_RENDER_TARGET;
+  halStream.producerUsage = static_cast<BufferUsage>(
+      static_cast<int64_t>(stream.usage) |
+      static_cast<int64_t>(BufferUsage::CAMERA_OUTPUT) |
+      static_cast<int64_t>(BufferUsage::GPU_RENDER_TARGET));
+
   halStream.supportOffline = false;
   return halStream;
 }