MDBF-883 - CentOS 7 bintar compatibility with old buildbot

[RazvanLiviuVarzaru]

As part of the MDBF, I am preparing several (manual) changes to the centos-7-bintar container image, one of which will bump GnuTLS version to 3.7.x, as in buildbot.mariadb.net

GNUTLS_NO_SIGNAL flag was introduced in GnuTLS 3.4.x so there's no need to disable the macro anymore. (the flag is not present in buildbot.mariadb.net configuration)

More on that, from my tests << 10.11 >> (thanks @cvicentiu for help) disabling the macro will cause the compilation to fail when using the newer GnuTLS (static library).
<command-line>:0:18: error: expected identifier before numeric constant.

Important notes:
This code change should only be deployed in Production when the updated centos7-bintar is published in quay, in this order:

• deploy code changes
• stop master-docker-nonstandard (where the builder is defined)
• update image on quay
• start master-docker-nonstandard

I will probably deploy this change manually because there are some pending
other changes which need to be tested and given the BLOCKER
status of the MDBF, it should be deployed ASAP.

[grooverdan]

I see from MDBF task that the gnutls is a static library build so this looks acceptable.

[RazvanLiviuVarzaru]

@cvicentiu @grooverdan
I've added c9852ce to solve builds on 11.7/11.8. Please see also the commit message for more details.

[grooverdan]

if you haven't tested main - after MariaDB/server#3758 might be a good revisit. Some other builders are before gcc 9 so I'm not expecting too much trouble.

[RazvanLiviuVarzaru]

@cvicentiu @grooverdan I've added c9852ce to solve builds on 11.7/11.8. Please see also the commit message for more details.

@cvicentiu
I removed the commit mentioned above, returned to the old GCC.
You can inspect the following image, look for /changelog

quay.io/mariadb-foundation/bb-worker:dev_centos7-bintar

I restricted this builder to run for >= 11.7
buildbot.mariadb.net does it too:
MariaDB/mariadb.org-tools@437b1f6

[RazvanLiviuVarzaru]

@cvicentiu I added 9b0e12d
to remove dead code. Please see the commit message.

[cvicentiu]

Looks good to me.

The schedulers one is a little bit tricky to spot. I realized that the key for those schedulers is for the parent-builder-name to be a substring of the s_packages / s_bigtest builder names.

We really should make that more obvious.