[ARM] ebsa110: fix warnings generated by asm/arch/io.h

Remove two warnings:
drivers/serial/8250_early.c:136: warning: unused variable 'mapsize'
include/linux/io.h:47: warning: passing argument 1 of '__readb' discards qualifiers from pointer target type

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