Remove flag for bta_av_setconfig_rej_type_confusion

The flag has been soaked in Nextfood for more than a month.

Bug: 260230151
Bug: 341754333
Bug: 315241296
Test: m libbluetooth
Ignore-AOSP-First: security
Tag: #security
Change-Id: I4a7a97196e0949960856183e6899a9fc4d7b4d44