python-incremental: add host variant

A host variant of the python-incremental package will be needed for
the python-treq package.

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

package/python-incremental/python-incremental.mk

@@ -12,3 +12,4 @@ PYTHON_INCREMENTAL_LICENSE = MIT
 PYTHON_INCREMENTAL_LICENSE_FILES = LICENSE
 
 $(eval $(python-package))
+$(eval $(host-python-package))