audio flinger: fix use of global effect buffer

When float mixing format is enabled, audio effects use a specific
buffer in 16 bit format. This buffer was not enabled when only
global effects were present resulting in the mixer accumulating directly
to the output sink buffer.

Bug: 16202259.
Change-Id: I3537d36c63196d97772f0ab22dd31d04dfa7fdd6
1 file changed