staging: spi: mt7621: Clean up excessive header usage

This patch removes unnecessary header includes and sorts the remaining
ones alphabetically.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Mark Brown <broonie@kernel.org>
Cc: Sankalp Negi <sankalpnegi2310@gmail.com>
Cc: Chuanhong Guo <gch981213@gmail.com>
Cc: John Crispin <john@phrozen.org>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/mt7621-spi/spi-mt7621.c

@@ -11,19 +11,13 @@
  *   Copyright (C) 2007-2008 Marvell Ltd.
  */
 
-#include <linux/init.h>
-#include <linux/module.h>
 #include <linux/clk.h>
-#include <linux/err.h>
 #include <linux/delay.h>
 #include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
 #include <linux/reset.h>
 #include <linux/spi/spi.h>
-#include <linux/of_device.h>
-#include <linux/platform_device.h>
-#include <linux/swab.h>
-
-#include <ralink_regs.h>
 
 #define SPI_BPW_MASK(bits) BIT((bits) - 1)