clk: qcom: dispcc-sm8250: Make clk_init_data and pll_vco const

The clk_init_data and pll_vco structures are never modified, make
them const.

Signed-off-by: Satya Priya Kakitapalli <quic_skakitap@quicinc.com>
Link: https://lore.kernel.org/r/20240201-dispcc-sm8150-v1-1-cbeb89015e5d@quicinc.com


Signed-off-by: Bjorn Andersson <andersson@kernel.org>