package/python-iso8601: use poetry setup type

Use the new poetry setup type which automatically pulls in the
host-python-poetry-core dependency.

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/python-iso8601/python-iso8601.mk

@@ -7,9 +7,8 @@
 PYTHON_ISO8601_VERSION = 2.1.0
 PYTHON_ISO8601_SOURCE = iso8601-$(PYTHON_ISO8601_VERSION).tar.gz
 PYTHON_ISO8601_SITE = https://files.pythonhosted.org/packages/b9/f3/ef59cee614d5e0accf6fd0cbba025b93b272e626ca89fb70a3e9187c5d15
-PYTHON_ISO8601_SETUP_TYPE = pep517
+PYTHON_ISO8601_SETUP_TYPE = poetry
 PYTHON_ISO8601_LICENSE = MIT
 PYTHON_ISO8601_LICENSE_FILES = LICENSE
-PYTHON_ISO8601_DEPENDENCIES = host-python-poetry-core
 
 $(eval $(python-package))