package/python-packaging: fix host variant

The host variant of python-packaging was added in commit
4cc445fd5fbb83c2b55f679f3d92223f34f214cb, but has two missing things:

- It's a python3 only package, so it should have
  HOST_PYTHON_PACKAGING_NEEDS_HOST_PYTHON = python3

- It depends on the pyparsing module, so it should have a dependency
  on it.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/python-packaging/python-packaging.mk

@@ -10,6 +10,8 @@ PYTHON_PACKAGING_SITE = https://files.pythonhosted.org/packages/df/86/aef78bab3a
 PYTHON_PACKAGING_SETUP_TYPE = setuptools
 PYTHON_PACKAGING_LICENSE = Apache-2.0 or BSD-2-Clause
 PYTHON_PACKAGING_LICENSE_FILES = LICENSE LICENSE.APACHE LICENSE.BSD
+HOST_PYTHON_PACKAGING_NEEDS_HOST_PYTHON = python3
+HOST_PYTHON_PACKAGING_DEPENDENCIES = host-python-pyparsing
 
 $(eval $(python-package))
 $(eval $(host-python-package))