Adds device tree bindings for SMPro MFD driver found on the Mt.Jade
hardware reference platform with Ampere's Altra Processor family.

The SMpro co-processor on Ampere Altra processor family is to monitor
and report various data included hwmon-related info, RAS errors, and
other miscellaneous information.
Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20221031024442.2490881-2-quan@os.amperecomputing.com