Add linux/ppc64le Arch back for magtape-init images

[phenixblue]

What would you like to be added:

Add support for building linux/ppc64le architecture container images for the magtape-init container.

Why is this needed:

Support for the linux/ppc64le arch was removed during the v2.4.0 release cycle for MagTape due to an issue encountered in release CI that blocked the release. This seems to be related to the cryptography library specifically.

Logs from CI run:

#27 489.6 Failed to install some dependency or packages.  The following have failed installation and attempted retry: [Requirement(_name='cryptography', vcs=None, req=NamedRequirement(name='cryptography', version='==37.0.2', req=Requirement.parse('cryptography==37.0.2'), extras=[], editable=False, _parsed_line=<Line (editable=False, name=cryptography, path=None, uri=None, extras=(), markers=None, vcs=None, specifier===37.0.2, pyproject=None, pyproject_requires=None, pyproject_backend=None, ireq=cryptography==37.0.2)>), markers=None, _specifiers='==37.0.2', index='pypi', editable=False, hashes=frozenset({'sha256:ef15c2df7656763b4ff20a9bc4381d8352e6640cfeb95c2972c38ef508e75181', 'sha256:aeaba7b5e756ea52c8861c133c596afe93dd716cbcacae23b80bc238202dc023', 'sha256:31fe38d14d2e5f787e0aecef831457da6cec68e0bb09a35835b0b44ae8b988fe', 'sha256:3c81599befb4d4f3d7648ed3217e00d21a9341a9a688ecdd615ff72ffbed7336', 'sha256:59b281eab51e1b6b6afa525af2bd93c16d49358404f814fe2c2410058623928c', 'sha256:0cc20f655157d4cfc7bada909dc5cc228211b075ba8407c46467f63597c78178', 'sha256:a7d5137e556cc0ea418dca6186deabe9129cee318618eb1ffecbd35bee55ddc1', 'sha256:46f4c544f6557a2fefa7ac8ac7d1b17bf9b647bd20b16decc8fbcab7117fbc15', 'sha256:471e0d70201c069f74c837983189949aa0d24bb2d751b57e26e3761f2f782b8d', 'sha256:1f3bfbd611db5cb58ca82f3deb35e83af34bb8cf06043fa61500157d50a70982', 'sha256:a68254dd88021f24a68b613d8c51d5c5e74d735878b9e32cc0adf19d1f10aaf9', 'sha256:3b8398b3d0efc420e777c40c16764d6870bcef2eb383df9c6dbb9ffe12c64452', 'sha256:95e590dd70642eb2079d280420a888190aa040ad20f19ec8c6e097e38aa29e06', 'sha256:093cb351031656d3ee2f4fa1be579a8c69c754cf874206be1d4cf3b542042804', 'sha256:731c8abd27693323b348518ed0e0705713a36d79fdbd969ad968fbef0979a7e0', 'sha256:2bd1096476aaac820426239ab534b636c77d71af66c547b9ddcd76eb9c79e004', 'sha256:f8ec91983e638a9bcd75b39f1396e5c0dc2330cbd9ce4accefe68717e6779e0a', 'sha256:dc26bb134452081859aa21d4990474ddb7e863aa39e60d1592800a8865a702de', 'sha256:1b9362d34363f2c71b7853f6251219298124aa4cc2075ae2932e64c91a3e2717', 'sha256:f224ad253cc9cea7568f49077007d2263efa57396a2f2f78114066fd54b5c68e', 'sha256:e53258e69874a306fcecb88b7534d61820db8a98655662a3dd2ec7f1afd9132f', 'sha256:419c57d7b63f5ec38b1199a9521d77d7d1754eb97827bbb773162073ccd8c8d4'}), extras=(), abstract_dep=None, _line_instance=<Line (editable=False, name=cryptography, path=None, uri=None, extras=(), markers=None, vcs=None, specifier===37.0.2, pyproject=None, pyproject_requires=None, pyproject_backend=None, ireq=cryptography==37.0.2)>, _ireq=None)]