clk: qcom: dispcc-kona: Add support for 7nm C-PHY shadow clock

Add support for 7nm DSI PLL C-PHY shadow clocks, which
will be used during dynamic dsi clock switch.

Change-Id: Ia5816874a1d58faa87744abdf98235170f8781ed
Signed-off-by: Harigovindan P <harigovi@codeaurora.org>