Add module test for g762 driver

Note that we can not really test much besides reading/writing registers
since the clock frequency is 0 by default, resulting in most speed values
to be reported as 0.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add module test for tmp421 driver

Signed-off-by: Guenter Roeck <linux@roeck-us.net>