drm/panfrost: clean headers in devfreq

Don't include not required headers and sort them.
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200710095409.407087-3-peron.clem@gmail.com

drivers/gpu/drm/panfrost/panfrost_devfreq.c

 // SPDX-License-Identifier: GPL-2.0
 /* Copyright 2019 Collabora ltd. */
+
+#include <linux/clk.h>
 #include <linux/devfreq.h>
 #include <linux/devfreq_cooling.h>
 #include <linux/platform_device.h>
 #include <linux/pm_opp.h>
-#include <linux/clk.h>
-#include <linux/regulator/consumer.h>
 
 #include "panfrost_device.h"
 #include "panfrost_devfreq.h"
-#include "panfrost_features.h"
-#include "panfrost_issues.h"
-#include "panfrost_gpu.h"
-#include "panfrost_regs.h"
 
 static void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev)
 {