OCI Runtime Specification v1.2.1

This is the first patch release of the v1.2.z series of the Open
Container Initative Runtime Specification. It primarily includes a
series of minor fixes as well as new support for the specification of
the CPU affinity of container processes.

 + zOS updates (#1273)
 + Add support for windows CPU affinity (#1258)
 + specs-go: sync SCMP_ARCH_* constants with libseccomp main (#1229)
 + Add CPU affinity to executed processes (#1253, #1261)
 + config-linux: describe the format of cpus and mems (#1253)
 * Fix description of errnoRet in Seccomp (#1277)
 * config-linux: update for libseccomp v2.6.0 (#1276)
 * Correct `prestart` hook description in summary (#1275)
 * MAINTAINERS: move vbatts to EMERITUS (#1248)

 Thanks to the following contributors for making this release possible:

 * Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
 * Austin Vazquez <macedonv@amazon.com>
 * Kaita Nakamura <kaita.nakamura0830@gmail.com>
 * Kershaw Mehta <kershaw@us.ibm.com>
 * Kijima Daigo <norimaking777@gmail.com>
 * Kir Kolyshkin <kolyshkin@gmail.com>
 * Kirtana Ashok <kiashok@microsoft.com>
 * Lei Wang <ssst0n3@gmail.com>
 * Neil Johnson <najohnsn@us.ibm.com>
 * Patrickuuuu <hank93513@gmail.com>
 * Sebastiaan van Stijn <github@gone.nl>
 * Tianon Gravi <admwiggin@gmail.com>
 * Toru Komatsu <k0ma@utam0k.jp>
 * Vincent Batts <vbatts@hashbangbash.com>

Vote-Results: +8 -0 *3 (#1278)
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>