Add pins, groups, and functions for the SPI Multi I/O Bus Controller
(RPC-IF) to the R8A77995 PFC driver.  They are to be used when a QSPI
Flash, Octal-SPI Flash, or HyperFlash is connected.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/19a3bccd0ec830846578a38b4c80dccb195109a0.1648547080.git.geert+renesas@glider.be