arm64: dts: marvell: armada-37xx: add a crypto node

This patch adds a crypto node describing the EIP97 engine found in
Armada 37xx SoCs. The cryptographic engine is enabled by default.

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