pulse - Fix capture problem
pulse - Fix capture problem

In pulse_start(), pa_stream_trigger() may return NULL for the capture
stream, and this caused -EIO error.
Allow now pa_stream_trigger() returning NULL.

Signed-off-by: Takashi Iwai <4596b3305151c7ee743192a95d394341e3d3b644@suse.de>

Themaister/alsa-plugins-rsound,Distrotech/alsa-plugins,Distrotech/alsa-plugins,Distrotech/alsa-plugins