audioflinger: Bind new mixer code to the resampler property

Don't try to use the new mixer mode if af.resampler.quality is set,
since they're incompatible. It's recommended that devices switch
by dropping the property though.

Change-Id: I18179799361108776a3a1e051bc0e23cd480fa10
Revert "audioflinger: Bind new mixer code to the resampler property"

This reverts commit 9094602d5448482e63da2f56f8c637652a9e1a58.

Change-Id: I9f569082051916cd885c1bd140d5a2a766703407