Merge branch 'lab-general' of github.com:Rockbox-Chinese-Community/Rockbox-RCC into lab-general
Re-add AA-Tube and surround DSP

Fix buffer overflow when playing .flac files and adjust to apply
surround and AA-Tube dsp before crossfeed

Change-Id: Ida04aeb64a162e5b76235407ad93aa47482e59e0

revert remove Surround and aa-tube

fix flac conflic (surround), apply to both channel(aa-tube)
Merge branch 'lab-general' into lab-android