ARM: dts: k2g: Add UART 1 and 2 instances

Add DT nodes for two other UART instances of 66AK2G SoC.

Also add power domain and clock domain nodes to UART 0

Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>