dts: arm: ti: cc23x0: Add pinctrl support

Add support for pinctrl to cc23x0 SoC.

Signed-off-by: Lars Thalian Morstad <l-morstad@ti.com>
Signed-off-by: Vebjorn Myklebust <v.myklebust@ti.com>
Signed-off-by: Stoyan Bogdanov <sbogdanov@baylibre.com>
Signed-off-by: Julien Panis <jpanis@baylibre.com>