pinctrl: sh-pfc: Rename PINMUX_IPSR_DATA() to PINMUX_IPSR_GPSR()

This macro describes a pinmux configuration that needs configuration in
both a Peripheral Function Select Register (IPSR) and in a
GPIO/Peripheral Function Select Register 1 (GPSR). Reflect that in the
macro name for clarity.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>