Feature Request - Make TRSYNC_TIMEOUT in mcu.py user configurable

[reapola]

Issue

When using canbus or multiple MCUs sometimes during homing or operations which requires MCUs working in unison a timeout can happen. Currently this is coded as 0.025.

E.g. Homing - Communication timeout during homing probe

Workaround

Open up the timout value of TRSYNC_TIMEOUT in mcu.py to 0.05 either by editing directly or using rootiest script https://github.com/rootiest/zippy-klipper_config/blob/master/scripts/mcu_timing.sh to partially automate it.

However any changes to mcu.py get reverted on a pull.

Proposed Change

Make TRSYNC_TIMEOUT a variable