package/python-inflection: python3 is also needed for host

Commit ac120d277704fb212654356a6d2a2ff7be90737a forgot to set
HOST_PYTHON_INFLECTION_NEEDS_HOST_PYTHON

Fixes:
 - http://autobuild.buildroot.org/results/b0f7e56fd1dfe891396adc2b232a2663a9715196

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/python-inflection/python-inflection.mk

@@ -10,6 +10,7 @@ PYTHON_INFLECTION_SITE = https://files.pythonhosted.org/packages/e1/7e/691d061b7
 PYTHON_INFLECTION_SETUP_TYPE = setuptools
 PYTHON_INFLECTION_LICENSE = MIT
 PYTHON_INFLECTION_LICENSE_FILES = LICENSE
+HOST_PYTHON_INFLECTION_NEEDS_HOST_PYTHON = python3
 
 $(eval $(python-package))
 $(eval $(host-python-package))