python-jaraco-classes: add missing dependency

python-jaraco-classes needs host-python-setuptools-scm.

Fixes:
http://autobuild.buildroot.net/results/3a7000002b86663a56c0341d192f131a4a8f4936
http://autobuild.buildroot.net/results/553d6fdeb6ea5359b1c7d4eeb844da7a588f02e7

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

package/python-jaraco-classes/python-jaraco-classes.mk

@@ -10,5 +10,6 @@ PYTHON_JARACO_CLASSES_SITE = https://pypi.python.org/packages/b3/ce/031a6004619c
 PYTHON_JARACO_CLASSES_LICENSE = MIT
 PYTHON_JARACO_CLASSES_LICENSE_FILES = LICENSE
 PYTHON_JARACO_CLASSES_SETUP_TYPE = setuptools
+PYTHON_JARACO_CLASSES_DEPENDENCIES = host-python-setuptools-scm
 
 $(eval $(python-package))