spi: mediatek: add linux/io.h include file

mediatek spi driver uses readl/writel, so add linux/io.h,
even so it's implicitly imported by spi/spi.h

Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
1 file changed