ARM: dts: msm: update ADC channels for holi-pm6125

Delete PMR735A and PMR735B ADC channels from PMK8350's list
of ADC channels, and xo_therm on PM6125 VADC, as they are not
used for holi-pm6125.

Change-Id: Ie2252f9e31236bf794b25bef6250bbd406d327ce