misc: move FLASH_MINOR into miscdevice.h and fix conflicts

FLASH_MINOR is used in both drivers/char/nwflash.c and
drivers/sbus/char/flash.c with conflict minor numbers.

Move all the definitions of FLASH_MINOR into miscdevice.h.
Rename FLASH_MINOR for drivers/char/nwflash.c to NWFLASH_MINOR
and FLASH_MINOR for drivers/sbus/char/flash.c to SBUS_FLASH_MINOR.

Link: https://lore.kernel.org/lkml/20200120221323.GJ15860@mit.edu/t/Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "David S. Miller" <davem@davemloft.net>
Link: https://lore.kernel.org/r/20200311071654.335-3-zhenzhong.duan@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm/include/asm/nwflash.h

@@ -2,7 +2,6 @@
 #ifndef _FLASH_H
 #define _FLASH_H
 
-#define FLASH_MINOR		 160	/* MAJOR is 10 - miscdevice */
 #define CMD_WRITE_DISABLE	 0
 #define CMD_WRITE_ENABLE	 0x28
 #define CMD_WRITE_BASE64K_ENABLE 0x47

drivers/char/nwflash.c

@@ -576,7 +576,7 @@ static const struct file_operations flash_fops =
 
 static struct miscdevice flash_miscdev =
 {
-	FLASH_MINOR,
+	NWFLASH_MINOR,
 	"nwflash",
 	&flash_fops
 };

drivers/sbus/char/flash.c

@@ -31,8 +31,6 @@ static struct {
 	unsigned long busy;		/* In use? */
 } flash;
 
-#define FLASH_MINOR	152
-
 static int
 flash_mmap(struct file *file, struct vm_area_struct *vma)
 {
@@ -157,7 +155,7 @@ static const struct file_operations flash_fops = {
 	.release =	flash_release,
 };
 
-static struct miscdevice flash_dev = { FLASH_MINOR, "flash", &flash_fops };
+static struct miscdevice flash_dev = { SBUS_FLASH_MINOR, "flash", &flash_fops };
 
 static int flash_probe(struct platform_device *op)
 {

include/linux/miscdevice.h

@@ -30,12 +30,14 @@
 #define SUN_OPENPROM_MINOR	139
 #define DMAPI_MINOR		140	/* unused */
 #define NVRAM_MINOR		144
+#define SBUS_FLASH_MINOR	152
 #define SGI_MMTIMER		153
 #define PMU_MINOR		154
 #define STORE_QUEUE_MINOR	155	/* unused */
 #define LCD_MINOR		156
 #define AC_MINOR		157
 #define BUTTON_MINOR		158	/* Major 10, Minor 158, /dev/nwbutton */
+#define NWFLASH_MINOR		160	/* MAJOR is 10 - miscdevice */
 #define ENVCTRL_MINOR		162
 #define I2O_MINOR		166
 #define UCTRL_MINOR		174