arm64: dts: Add ARM PL330 DMA DT node for NS2

We have one ARM PL330 DMA instance with 8 channels in
NS2 SoC. Let's enable it for NS2 in NS2 DT.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <rjui@broadcom.com>
Reviewed-by: Pramod KUMAR <pramodku@broadcom.com>
Reviewed-by: Scott Branden <sbranden@broadcom.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>