drm_hwcomposer: Initialize DrmProperty type_ member

Initialize it to an invalid value instead of INT.

Change-Id: I5d75b9a3696a748d6352d918263b482034a22001
Signed-off-by: Sean Paul <seanpaul@chromium.org>
diff --git a/drmproperty.h b/drmproperty.h
index eb5fcb5..1ebd665 100644
--- a/drmproperty.h
+++ b/drmproperty.h
@@ -27,6 +27,7 @@
 enum DrmPropertyType {
   DRM_PROPERTY_TYPE_INT,
   DRM_PROPERTY_TYPE_ENUM,
+  DRM_PROPERTY_TYPE_INVALID,
 };
 
 class DrmProperty {