In order for consumers of RPMCC XO clock to probe successfully
their parent needs to be feed with reference clock to obtain proper rate,
add fixed xo-board clock and supply it to rpmcc to make consumers happy.
Frequency setting is left per board basis just like on other recent trees.

Fixes: 0484d3ce ("arm64: dts: qcom: Add DTS for MSM8976 and MSM8956 SoCs")
Fixes: ff7f6d34 ("arm64: dts: qcom: Add support for SONY Xperia X/X Compact")
Signed-off-by: Adam Skladowski <a39.skl@gmail.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
[bjorn: Squashed the two patches]
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230302123051.12440-1-a39.skl@gmail.com
Link: https://lore.kernel.org/r/20230302123051.12440-2-a39.skl@gmail.com