MHAIOParser: Fix timeout on stop request
MHAIOParser: Fix timeout on stop request

Summary:
MHAIOParser: Fix timeout on stop request
Closes T716

Test Plan:
Run e.g. `mha --interactive iolib=MHAIOParser mhalib=identity cmd=start cmd=quit`
and verify disappearance of error message

Reviewers: tobias

Reviewed By: tobias

Subscribers: #openmha

Maniphest Tasks: T716

Differential Revision: https://dev.openmha.org/D372

HoerTech-gGmbH/openMHA,HoerTech-gGmbH/openMHA,HoerTech-gGmbH/openMHA,HoerTech-gGmbH/openMHA,HoerTech-gGmbH/openMHA,HoerTech-gGmbH/openMHA,HoerTech-gGmbH/openMHA,HoerTech-gGmbH/openMHA