iface-modem: fix signal check running when disabled
signal_check_running
is set TRUE
when first refreshing the signal, but never set to FALSE
when disabling the signal check, which will result in the signal check not being enabled when calling the refresh signal function again after disabling the signal check.
/* Don't refresh if we're already doing it */
if (priv->signal_check_running) {
mm_obj_dbg (self, "periodic signal check refresh ignored: check already running");
return;
}
mm_obj_dbg (self, "periodic signal check refresh requested");
priv->signal_check_running = TRUE;