[qt5-base] mysql plugin added

[jepessen]

The pull request creates the qsqlmysql database plugin for qt5-base.

It adds a dependency from libmysql in order to build it before the plugin since it's requested.

[jepessen]

Hi.
It's possible in some way to see the error logs written during the tests, like this one?

Because I can try to fix for all configuration that I have, I can't test every of them (I don't have linux machines or osx for example) so I cannot perform local tests and I cannot check what's wrong with them.

[JackBoosY]

@jepessen

1. Click Details in pipeline test results below.
2. Click View more details on Azure Pipelines
3. Click [NUM] artifacts produced
4. Click the three vertical dots on the far right of the error log entry
5. Click Download artifacts

[jepessen]

@JackBoosY ok thanks a lot

[JackBoosY]

cc @Neumann-A for review this PR.

[JackBoosY]

@Neumann-A said this should be added as a qt5-base feature.

[jepessen]

Ok I'll add it as feature ASAP.

[jepessen]

I've set the mysql plugin as qt5-base feature.

[JackBoosY]

LGTM.

[jepessen]

I think it should be there, because there's already sqlite and postgresql. Since they are all plugin, or we put them all together at once or none of them in my opinion. There's no reason to include postgresql plugin by default and not mysql, or vice versa. Since postgresql plugin is already installed by default with qt5 I've followed the same logic (it was the reason why I did't added it with a separate feature at start).

[JackBoosY]

No...no... the mysql doesn't support x86 now, so if you try to install qt5 directly, it will shows us:

CMake Error at scripts/cmake/vcpkg_fail_port_install.cmake:97 (message):
  Architecture 'x86' not supported by libmysql!

I will open a PR to remove the default feature.