set_quirks has a "if (!interface) return;" check at its beginning and
interface always is NULL when set_quirks is called from find_quirks,
so it is a no-op and we can drop it.

This also allows dropping the "if (!interface) return;" from set_quirks
since set_quirks now always is called with interface != NULL.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20201019185628.264473-1-hdegoede@redhat.com