v4l2object: Fix try/s_fmt errors
v4l2object: Fix try/s_fmt errors

According to the spec,TRY_FMT cannot return EBUSY, though it can
return EINVAL if it was not possible to update the format to
something supported.

https://bugzilla.gnome.org/show_bug.cgi?id=785156

pexip/gst-plugins-good,GStreamer/gst-plugins-good,GrokImageCompression/gst-plugins-good,pexip/gst-plugins-good,pexip/gst-plugins-good,GStreamer/gst-plugins-good,StreamUtils/gst-plugins-good,StreamUtils/gst-plugins-good,GrokImageCompression/gst-plugins-good,StreamUtils/gst-plugins-good,GStreamer/gst-plugins-good,GStreamer/gst-plugins-good,pexip/gst-plugins-good,pexip/gst-plugins-good,StreamUtils/gst-plugins-good,GrokImageCompression/gst-plugins-good,GrokImageCompression/gst-plugins-good