audioflinger: Remove effect from hal before closing.

- For non pinned effects, when the handle is removed the effect interface
  is closed, but this leads to not resetting the state of hal effects.
  Don't close the interface from here, as it will be handled in
  subsequent removeEffect_l.

- Clean up code related to removeHandle_l.

CRs-Fixed: 2746289
Bug: 163285058
Test: Solo tester with effects
Change-Id: I2a9b35f5f73e535afd4fe77823b9a8ba16271685