ARM: dts: microchip: Remove additional compatible string from PIO3 pinctrl nodes

ARM: dts: microchip: Remove additional compatible string from PIO3 pinctrl nodes

The driver data specific to each pinctrl GPIO bank compatible nodes are not
the same and declaring additional compatible string as fallback has no
specific purpose, hence, removing the additional compatible string from the
pinctrl nodes in DT to comply with atmel,at91-pinctrl.txt documentation.

Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20240814061315.112564-3-manikandan.m@microchip.com
Signed-off-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>