arm64: dts: ti: k3-am65: Add pinctrl regions

Add pinctrl regions for the main and wkup mmr.

The range for main pinctrl region contains a gap
at offset 0x2e4, and because of this, the pinctrl
range is split into two sections.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>