dpll: zl3073x: Fetch invariants during probe

dpll: zl3073x: Fetch invariants during probe

Several configuration parameters will remain constant at runtime,
so we can load them during probe to avoid excessive reads from
the hardware.

Read the following parameters from the device during probe and store
them for later use:

* enablement status and frequencies of the synthesizers and their
  associated DPLL channels
* enablement status and type (single-ended or differential) of input pins
* associated synthesizers, signal format, and enablement status of
  outputs

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://patch.msgid.link/20250704182202.1641943-7-ivecera@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>