leaudio: Make sure to use 2M PHY if possible.

LeAudio service configure ACL for 2M PHY on each reconnection.
Unfortunatelly it might happen before stack reads the Remote Supported
Features.
With this patch if the first try did not succeed, we try again when
encryption is enabled.

Bug: 330481628
Test: atest bluetooth_le_audio_client_test
Flag: Exempt, regression tested with unit tests, new test added
Change-Id: If1424436b45b912dcce0369c99d45f3e7168bd0f