ARM: dts: Unify pinctrl-single pin group nodes for keystone

ARM: dts: Unify pinctrl-single pin group nodes for keystone

We want to unify the pinctrl-single pin group nodes to use naming "pins".
Otherwise non-standad pin group names will add make dtbs checks errors
when the pinctrl-single yaml binding gets merged.

Cc: Conor Dooley <conor+dt@kernel.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230523074845.59433-1-tony@atomide.com
Signed-off-by: Nishanth Menon <nm@ti.com>