stack/a2dp: Improve the declaration of tA2Dp_STATUS

- add error codes from AVDTP and GAVDTP specifications
- document the source specification for each range of constants
- rename the error codes to match the specifications

Bug: 331817295
Test: m com.android.btservices
Flag: EXEMPT, no logical change
Change-Id: Ie9dc7a889bd2b299acfb9284378c3af8347a1b23