Yusuke Endoh de82439215 Do not use pthread_setaffinity_np on s390x
Looks like it randomly causes a segfault

https://rubyci.s3.amazonaws.com/rhel_zlinux/ruby-master/log/20231025T093302Z.fail.html.gz
```
[11186/26148] TestNetHTTP_v1_2#test_set_form/home/chkbuild/build/20231025T093302Z/ruby/tool/lib/webrick/httprequest.rb:197: [BUG] Segmentation fault at 0x000003ff1ffff000
ruby 3.3.0dev (2023-10-25T07:50:00Z master 526292d9fe) [s390x-linux]
```
2023-10-25 20:04:18 +09:00
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2023-06-12 18:23:48 +09:00
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2023-01-16 08:00:03 +09:00