DUBAI, Dec 23 (Reuters) - Etihad Airways will divest several support service businesses to a new aviation company owned by Abu Dhabi state holding firm ADQ and to Abu Dhabi National Exhibitions Company (ADNEC), a government media office said on Thursday. The deal would add to ADQ"s mobility and logistics portfolio, allow Etihad to capitalise on global travel market opportunities and boost Abu Dhabi"s aviation ecosystem, the office added.