[ARM] 3281/1: ixp4xx: export ixp4xx_exp_bus_size for modules

Patch from David Vrabel

Export ixp4xx_exp_bus_size so modules can use the IXP4XX_EXP_BUS_BASE(n) macro.

Also, fix a printk format warning.

Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>