ARM: shmobile: sh73a0: Support sparse GPIO numbers

The SH73A0 SoC has sparse GPIO numbers. Declare the pin numbers ranges
in the PFC SoC data and use the pin numbers in the GPIO API.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>