A California Highway Patrol spokesman in Anaheim said his agency would probably endorse a lowering of the legal limit defining drunkenness from 0.1% blood-alcohol level to 0.05%. The spokesman added that the CHP also would probably support legislation to confiscate driver's licenses of people arrested for drunk driving. A policy-making body of the 34,000-member California Medical Assn. called for such legislation during its three-day conference in Anaheim. The proposal to lower the legal maximum for blood alcohol was made by Santa Ana psychiatrist David Geddes.