all(style) : fix linter issues for errcheck, ineffassign, unused and fix errors

[gen2thomas]

Solved issues and/or description of the change

Activate linters "errcheck", "ineffassign" and "unused" and fix all linter issues. For "errcheck" many adjustments were needed. In unit tests all errors were dropped. For productive code fix was done in the following order:

• try return error, if not possible
• panic on error, if not possible or useful
• log and drop error

In addition following errors were found:

• Fixed: stopping of robots returned on first error, so further robots remain started
• Dji Tello: wifiMessage and lightMessage not working #948
• Fixed: log.Fatal before return nil or error in ble to only return error
• Fixed: return the wrong err object in curie/imu_driver handleEvent()
• Fixed: Improve error handling in joystick driver #574

Some format changes were done automatically by IDE.

Manual test

• Linux, Tinkerboard (i2c and PWM)

Checklist

• The PR's target branch is 'hybridgroup:dev'
• New and existing unit tests pass locally with my changes (e.g. by run make test)
• No linter errors exist locally (e.g. by run make fmt_check)
• I have performed a self-review of my own code