package/python-service-identity: add missing python-cryptography dependency

The last version bump removed python-pyopenssl runtime dependency but
doing so also removed the python-cryptography runtime depdency [1] that
is actually a direct runtime dependency.

While at it, update BR2_PACKAGE_HOST_RUSTC_TARGET_ARCH_SUPPORTS
dependency comment.

[1] 6008f2b1b901be1374ac201b5e560cca61b4b61e

Fixes:
https://gitlab.com/buildroot.org/buildroot/-/jobs/6477656983 (TestPythonPy3ServiceIdentity)

Cc: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
1 file changed