* Ramadi tribes turn on al Qaeda fighters
* Anbar violence is test of strength for Maliki
* Syria war feeding instability in Iraq
By Suadad al-Salhy
BAGHDAD, Jan 3 (Reuters) - Dressed in black and waving al Qaeda flags, Islamist insurgents battled tribesmen for control of the Iraqi city of Ramadi on Friday, while in Fallujah they grabbed loudspeakers after weekly prayers to call for ...