qcom: clock-cpu-8994: Configure (secure) CCI & debug muxes

In 8994V1, the CCI and debug mux registers are inaccessible
to the non-secure world. Add support to read and write to
these registers via SCM calls.

Change-Id: Id6b0d14f1993f18e4c7e13090a64b44e9f92bfac
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>