hwmon: (asus-ec-sensors) add driver for ASUS EC

This driver provides the same data as the asus_wmi_ec_sensors driver
(and gets it from the same source) but does not use WMI, polling
the ACPI EC directly.

That provides two enhancements: sensor reading became quicker (on some
systems or kernel configuration it took almost a full second to read
all the sensors, that transfers less than 15 bytes of data), the driver
became more flexible. The driver now relies on ACPI mutex to lock access
to the EC in the same way as the WMI code does.

Signed-off-by: Eugene Shalygin <eugene.shalygin@gmail.com>
Link: https://lore.kernel.org/r/20220124015658.687309-2-eugene.shalygin@gmail.com
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Denis Pauk <pauk.denis@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>