[MTD] Make init_sbc82xx_flash function static

The function init_sbc82xx_flash is needlessly defined global in
drivers/mtd/maps/wr_sbc82xx_flash.c, and this patch makes it static.
Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@movial.fi>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/maps/wr_sbc82xx_flash.c

@@ -74,7 +74,7 @@ do {								\
 	}							\
 } while (0);
 
-int __init init_sbc82xx_flash(void)
+static int __init init_sbc82xx_flash(void)
 {
 	volatile memctl_cpm2_t *mc = &cpm2_immr->im_memctl;
 	int bigflash;