The BCM958625HR board has 2GB of RAM available.  Increase the amount
from 512MB to 2GB and add the device type to the memory entry.

Fixes: 9a4865d4 ("ARM: dts: NSP: Specify RAM amount for BCM958625HR board")
Signed-off-by: Jon Mason <jon.mason@broadcom.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>