Remove 96.0 and 88.2 kHz sample rate from A2DP AAC capability

The A2DP AAC Source capabilty should not include 96.0 and 88.2 kHz
sample rate - those were included unintentionally without being tested.

Bug: 37968743
Test: A2DP AAC streaming
Change-Id: Ia3228d4d14d3288acfda42fbaf8ab248ae530b48
(cherry picked from commit e107473a)