USB: serial: constify static arrays

Declare three immutable static driver arrays as const.
Signed-off-by: Johan Hovold <johan@kernel.org>

drivers/usb/serial/io_edgeport.c

@@ -2839,7 +2839,7 @@ static int edge_startup(struct usb_serial *serial)
 	bool interrupt_in_found;
 	bool bulk_in_found;
 	bool bulk_out_found;
-	static __u32 descriptor[3] = {	EDGE_COMPATIBILITY_MASK0,
+	static const __u32 descriptor[3] = {	EDGE_COMPATIBILITY_MASK0,
 						EDGE_COMPATIBILITY_MASK1,
 						EDGE_COMPATIBILITY_MASK2 };
 

drivers/usb/serial/mos7720.c

@@ -1408,7 +1408,7 @@ struct divisor_table_entry {
 /* Define table of divisors for moschip 7720 hardware	   *
  * These assume a 3.6864MHz crystal, the standard /16, and *
  * MCR.7 = 0.						   */
-static struct divisor_table_entry divisor_table[] = {
+static const struct divisor_table_entry divisor_table[] = {
 	{   50,		2304},
 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */

drivers/usb/serial/usb_debug.c

@@ -17,7 +17,7 @@
 
 #define USB_DEBUG_MAX_PACKET_SIZE	8
 #define USB_DEBUG_BRK_SIZE		8
-static char USB_DEBUG_BRK[USB_DEBUG_BRK_SIZE] = {
+static const char USB_DEBUG_BRK[USB_DEBUG_BRK_SIZE] = {
 	0x00,
 	0xff,
 	0x01,