ARM: sun5i: add a cryptographic engine node

Add a node for the cryptographic engine that can be found on sun5i SoCs.
This cryptographic engine is compatible with the Allwinner cryptographic
accelerator driver.

Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>