ARM: Fix warning in sa1100-flash.c

drivers/mtd/maps/sa1100-flash.c: In function 'sa1100_probe_subdev':
drivers/mtd/maps/sa1100-flash.c:214: warning: format '%d' expects type 'int', but argument 3 has type 'uint64_t'

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>