No need to init packet as {0}
Merge pull request #5816 from raven02/patch-8

No need to init packet as 0
Custom BGM is fixed
Based on this commit https://github.com/hrydgard/ppsspp/pull/5828 on improvements to sceMp3
Custom BGM can be update now. Test on "Miku" is just all right :)
Merge pull request #5829 from kaienfr/new_Custom_BGM

Custom BGM is fixed
Parse MP3 header to correct set the channel and samplerate
Merge pull request #5830 from raven02/patch-9

Parse MP3 header to correct set the channel and samplerate