The built-in PPE engine has a dedicated clock for the EIP-197 crypto
engine.

So, since the required clock currently missing add support for it.
Signed-off-by: Robert Marko <robimarko@gmail.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220515210048.483898-5-robimarko@gmail.com