drm/vmwgfx: fix include notation and remove -Iinclude/drm flag

Include <drm/*.h> instead of relative path from include/drm, then
remove the -Iinclude/drm compiler flag.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1493009447-31524-18-git-send-email-yamada.masahiro@socionext.com
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf.c
index 77cb7c6..99a7f4a 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf.c
@@ -25,8 +25,9 @@
  *
  **************************************************************************/
 
+#include <drm/ttm/ttm_bo_api.h>
+
 #include "vmwgfx_drv.h"
-#include "ttm/ttm_bo_api.h"
 
 /*
  * Size of inline command buffers. Try to make sure that a page size is a