Changed the default configured sample rate for aptX/aptX-HD to 48.0kHz

Previously, the default configured sample rate for aptX and aptX-HD
was 44.1kHz. However, during AVDTP codec setup, the initial codec
setup to 44.1kHz was followed immediately with automatic codec
reconfiguration to 48.0kHz (if supported by the remote device)
so the highest possible sample rate will be used.

Changing the default sample rate to 48.0kHz eliminates the
transient initial codec setup of 44.1kHz, because it is unnecessary
and error-prone.

Bug: 69276823
Test: Manual: connect to aptX / aptX-HD headsets and examine the AVDTP codec
      configuration in the btsnoop logs.
Change-Id: I9e22365e0f07690c87503ea52fd9bb4d1ad4d5ff