I2C - unify i2cUnstick implementation, improve unstick a bit (#13541)
* I2C - unify i2cUnstick implemntation, improve unstick a bit
Three copies were spread in I2C implementations.
- i2cUnstick is a bit more carefull about clock stretching
- bus status is returned (return true when bus in idle state)
* fixup! I2C - unify i2cUnstick implemntation, improve unstick a bit
* fixup! I2C - unify i2cUnstick implemntation, improve unstick a bit
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Co-authored-by: Petr Ledvina <ledvinap@hp124.ekotip.cz>