libdrm: Add rotation property fields

From drm_crtc.h, for use with the plane "rotation" property

NOTE: These are legacy definitions for old code, similar
DRM_MODE_* mask values are defined in the upstream code.

Change-Id: I9240dede6a53817e6d8cedb31f6877312078b5ab
Signed-off-by: Sean Paul <seanpaul@chromium.org>
[jstultz: Added note about legacy definitions ]
Signed-off-by: John Stultz <john.stultz@linaro.org>
diff --git a/include/drm/drm_mode.h b/include/drm/drm_mode.h
index 5f9fadb..74368de 100644
--- a/include/drm/drm_mode.h
+++ b/include/drm/drm_mode.h
@@ -173,6 +173,19 @@
 		DRM_MODE_REFLECT_X | \
 		DRM_MODE_REFLECT_Y)
 
+
+/*
+ * Legacy definitions for old code that doesn't use
+ * the above mask definitions. Don't use in future code.
+ */
+/* rotation property bits */
+#define DRM_ROTATE_0   0
+#define DRM_ROTATE_90  1
+#define DRM_ROTATE_180 2
+#define DRM_ROTATE_270 3
+#define DRM_REFLECT_X  4
+#define DRM_REFLECT_Y  5
+
 /* Content Protection Flags */
 #define DRM_MODE_CONTENT_PROTECTION_UNDESIRED	0
 #define DRM_MODE_CONTENT_PROTECTION_DESIRED     1