python-twisted: enable Python 3 support

setup3.py will be automatically invoked from setup.py,
if executing on Python 3 platform.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/python-twisted/Config.in

@@ -1,6 +1,5 @@
 config BR2_PACKAGE_PYTHON_TWISTED
 	bool "python-twisted"
-	depends on BR2_PACKAGE_PYTHON
 	select BR2_PACKAGE_PYTHON_ZOPE_INTERFACE # runtime
 	help
 	  Twisted is an event-driven networking engine written in Python.