uboot-imx

MIPS: use inline directive for __in*s functions

All other IO accessor functions are using the
'inline' directive. Use that also for the __in*s
to make it consistent with the other variants.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>