drm: Add drm/drm_util.h header file

We have a bunch of neat little macros all over the place which should
move to kernel.h. But some of them died in bikesheds on lkml, and we
need a decent home for them.

Start out by moving the for_each_if macro there.

v2: Rename to drm_util.h instead (Dave&Sean)

Cc: Sean Paul <[e-mail]>
Acked-by: Sean Paul <[e-mail]>
Cc: Dave Airlie <[e-mail]>
Acked-by: Dave Airlie <[e-mail]>
Signed-off-by: Daniel Vetter <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/i915/i915_drv.h

···
 #include <drm/drm_gem.h>
 #include <drm/drm_auth.h>
 #include <drm/drm_cache.h>
+#include <drm/drm_util.h>
 
 #include "i915_params.h"
 #include "i915_reg.h"

drivers/gpu/drm/i915/intel_display.h

···
 #ifndef _INTEL_DISPLAY_H_
 #define _INTEL_DISPLAY_H_
 
+#include <drm/drm_util.h>
+
 enum pipe {
 	INVALID_PIPE = -1,
 

drivers/gpu/drm/i915/intel_ringbuffer.h

···
 #ifndef _INTEL_RINGBUFFER_H_
 #define _INTEL_RINGBUFFER_H_
 
+#include <drm/drm_util.h>
+
 #include <linux/hashtable.h>
 #include <linux/seqlock.h>
 

drivers/gpu/drm/nouveau/nouveau_connector.h

···
 #include <drm/drm_edid.h>
 #include <drm/drm_encoder.h>
 #include <drm/drm_dp_helper.h>
+#include <drm/drm_util.h>
+
 #include "nouveau_crtc.h"
 #include "nouveau_encoder.h"
 

include/drm/drmP.h

···
 	return true;
 }
 
-/* helper for handling conditionals in various for_each macros */
-#define for_each_if(condition) if (!(condition)) {} else
-
 #endif

include/drm/drm_atomic.h

···
 #define DRM_ATOMIC_H_
 
 #include <drm/drm_crtc.h>
+#include <drm/drm_util.h>
 
 /**
  * struct drm_crtc_commit - track modeset commits on a CRTC

include/drm/drm_atomic_helper.h

···
 #include <drm/drm_crtc.h>
 #include <drm/drm_modeset_helper_vtables.h>
 #include <drm/drm_modeset_helper.h>
+#include <drm/drm_util.h>
 
 struct drm_atomic_state;
 struct drm_private_obj;

include/drm/drm_connector.h

···
 #include <linux/ctype.h>
 #include <linux/hdmi.h>
 #include <drm/drm_mode_object.h>
+#include <drm/drm_util.h>
 
 #include <uapi/drm/drm_mode.h>
 

include/drm/drm_encoder.h

···
 #include <drm/drm_crtc.h>
 #include <drm/drm_mode.h>
 #include <drm/drm_mode_object.h>
+#include <drm/drm_util.h>
 
 struct drm_encoder;
 

include/drm/drm_plane.h

···
 #include <linux/ctype.h>
 #include <drm/drm_mode_object.h>
 #include <drm/drm_color_mgmt.h>
+#include <drm/drm_util.h>
 
 struct drm_crtc;
 struct drm_printer;

include/drm/drm_util.h

···
+/*
+ * Internal Header for the Direct Rendering Manager
+ *
+ * Copyright 2018 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef _DRM_UTIL_H_
+#define _DRM_UTIL_H_
+
+/* helper for handling conditionals in various for_each macros */
+#define for_each_if(condition) if (!(condition)) {} else
+
+#endif