- Only implement a single syncronous read/write function to read a byte,
since that's all we need currently
- Implement a compact IR_SENSOR probe for PAT9125
- Saves 242 bytes compared to PAT9125_SWI2C
Depending on the filament surface and moving speed, the PAT9125 sensor
can stop being able to track movement.
In such cases, instead of triggering false errors and/or relying on
previous states, read and use the exposure data off the sensor and
increase error counts only for poorly exposed images instead, which
is a good indicator of a far-away (or missing!) tracking surface.
