drm/qxl: 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/1493009447-31524-13-git-send-email-yamada.masahiro@socionext.com
diff --git a/drivers/gpu/drm/qxl/qxl_drv.c b/drivers/gpu/drm/qxl/qxl_drv.c
index abf7b83..c2fc201 100644
--- a/drivers/gpu/drm/qxl/qxl_drv.c
+++ b/drivers/gpu/drm/qxl/qxl_drv.c
@@ -31,9 +31,9 @@
 #include <linux/module.h>
 #include <linux/console.h>
 
-#include "drmP.h"
-#include "drm/drm.h"
-#include "drm_crtc_helper.h"
+#include <drm/drmP.h>
+#include <drm/drm.h>
+#include <drm/drm_crtc_helper.h>
 #include "qxl_drv.h"
 #include "qxl_object.h"