Better diagnosis if inductive sensor coil is not connected #952
Description
Currently if the inductive sensor coil is not connected on a TOOL1RR then the probe reading jumps between 999999 and 1048575, MM122 reports the raw value as 268435455 and the frequency 25.00MHz, and running M558.2 S-1 reports failure. We should have a clearer indication that the coil is not connected.