MFC r346431, r349872

r346431
Specify using Python2, these .py files have not been converted to use Python3
yet, but the default Python version in ports has been switched to 3.

Sponsored by: The FreeBSD Foundation

r349872
Correct definitions in sys.opencrypto.runtests.main for 32bit platform

Reviewed by: cem, jhb
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D20894