Add support for new RM4C Mini device ID: 0xa544

[kinsl4yer]

Device: Broadlink BestCon RM4C Mini (Also sold rebranded as Keemple Uniwersalny Sterownik Podczerwieni)
Unsupported Device ID: 0xa544

Description:
Home Assistant and python-broadlink currently throw an "Unsupported Device" error for the ID 0xa544.

Proposed Fix:
Please add 0xa544: ("RM4C mini", "Broadlink") to the rm4mini class in init.py.

Thank you!