pinctrl: rzn1: Do not select GENERIC_PIN{CTRL_GROUPS,MUX_FUNCTIONS}

The RZ/N1 pin control driver does not use pin groups or pin functions,
so there is no need to select GENERIC_PINCTRL_GROUPS or
GENERIC_PINMUX_FUNCTIONS.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200909131534.12897-2-geert+renesas@glider.be