Renesas MSIOF spi controller
Required properties:
- compatible : “renesas,sh-msiof” for SuperH or
"renesas,sh-mobile-msiof" for SH Mobile series
- reg : Offset and length of the register set for the device
- interrupts : interrupt line used by MSIOF
Optional properties:
- num-cs : total number of chip-selects
- renesas,tx-fifo-size : Overrides the default tx fifo size given in words
- renesas,rx-fifo-size : Overrides the default rx fifo size given in words