audio: Add a missing break to EffectsFactory::getAllDescriptors

Would the legacy HAL return -ENOENT while retrieving an effect,
the enumeration has to be aborted, and the effects queried so far
need to be returned. A missing 'break' was causing returning
no effects at all.

Bug: 117567478
Test: make
Change-Id: I7cc05004f88b39272d06d2ed33a0693f8e1e3d04