arm64: defconfig: enable Marvell CP110 comphy

The comphy is an hardware block giving access to common PHYs that can be
used by various other engines (Network, SATA, ...). This is used on
Marvell 7k/8k platforms for now. Enable the corresponding driver.

Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>