package/python-cryptography: add host variant

Since commit 0c7e30b43a5e98abfc8db521a6415b5a5c1c267f,
python-cryptography depends on python3. So python3-cryptography became
redundant at that point. As python3-cryptography is a host-only package,
while python-cryptography is a python-only package, add a host variant
to python-cryptography to be able to drop python3-cryptography.

Update ca-certificates to use host-python-cryptography instead of
host-python3-cryptography.

While at it, drop host-python3-pip and host-python3-six as these
dependencies are not needed. Indeed, pip was never a dependency of
cryptography and six is not a dependency with python3 and will be
dropped in version 3.4 and
https://github.com/pyca/cryptography/commit/e66db8079d3fbd0110e87ece1fd48f4bfd9e48b9

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

squash! package/python-cryptography: add host variant

package/ca-certificates/ca-certificates.mk

@@ -7,7 +7,7 @@
 CA_CERTIFICATES_VERSION = 20211016
 CA_CERTIFICATES_SOURCE = ca-certificates_$(CA_CERTIFICATES_VERSION).tar.xz
 CA_CERTIFICATES_SITE = https://snapshot.debian.org/archive/debian/20211022T144903Z/pool/main/c/ca-certificates
-CA_CERTIFICATES_DEPENDENCIES = host-openssl host-python3 host-python3-cryptography
+CA_CERTIFICATES_DEPENDENCIES = host-openssl host-python3 host-python-cryptography
 CA_CERTIFICATES_LICENSE = GPL-2.0+ (script), MPL-2.0 (data)
 CA_CERTIFICATES_LICENSE_FILES = debian/copyright
 

package/python-cryptography/python-cryptography.mk

@@ -14,5 +14,8 @@ PYTHON_CRYPTOGRAPHY_LICENSE_FILES = LICENSE LICENSE.APACHE LICENSE.BSD
 PYTHON_CRYPTOGRAPHY_CPE_ID_VENDOR = cryptography_project
 PYTHON_CRYPTOGRAPHY_CPE_ID_PRODUCT = cryptography
 PYTHON_CRYPTOGRAPHY_DEPENDENCIES = host-python-cffi openssl
+HOST_PYTHON_CRYPTOGRAPHY_NEEDS_HOST_PYTHON = python3
+HOST_PYTHON_CRYPTOGRAPHY_DEPENDENCIES = host-python3-cffi host-openssl
 
 $(eval $(python-package))
+$(eval $(host-python-package))