qcom_clk: add the qualcomm clock nodes for the IPQ4018

These clock nodes are used by the IPQ4018/IPQ4019 and derivatives.
They're also used by other 32 and 64 bit qualcomm parts; so it's
best to put these nodes here in a single qcom_clk driver and add
to it as we grow new Qualcomm SoC support.

Tested:

• IPQ4018, boot

Differential Revision: https://reviews.freebsd.org/D33665