Extend python3-pip to nativesdk because some nativesdk python3 packages
need it, e.g. nativesdk-python3-django from meta-python layer.
(From OE-Core rev: 31f1e5f438d19aa329e5f38b1ab4e7d521eff8a1)
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>