When /bin/sh isn't bash, the previous line always appears to succeed,
and modinfo's output is not redirected, because it actually runs
modinfo in the background (which always succeeds) then opens and closes
/dev/null without doing anything to it. This causes us to always think
that the v4l2loopback module is installed, even when it isn't.
This functionality can now be handled automatically because locale can
now be freed seaparately from obs_module_unload with
obs_module_free_locale, which is called automatically when the module is
being freed.