clk: qcom: clk-cpu-osm: Add OPP support for the L3 clock

Add logic to fill the L3 clock frequency-voltage mappings
to the OPP tables for the devfreq client to use.

Change-Id: Ie19be322d70757236680b4bf38708d24ace001e3
Signed-off-by: Deepak Katragadda <dkatraga@codeaurora.org>