ARM: dts: r9a06g032: Add pinctrl node

This provides a pinctrl driver for the Renesas R9A06G032 SoC

Based on a patch originally written by Michel Pollet at Renesas.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>