[gdal] update port to 2.3.2 and mysql support as port feature

[hlysunnaram]

This PR updates gdal port from 2.3.0 to 2.3.2.

It also removes libmysql from GDAL core dependencies and makes mysql support a port feature (related issue: #3793).

Two features are created:

• mysql-libmysql to add mysql support using libmysql
• mysql-libmariadb to add mysql support using libmariadb

mysql-libmysql is placed in Default-Features to keep previous compatibility.
However, one can choose between libmariadb or libmysql implementation or even no mysql support using feature selection:

vcpkg install gdal[core]
vcpkg install gdal[core,mysql-libmysql]
vcpkg install gdal[core,mysql-libmariadb]

Finally, this PR fixes build issue of libmariadb if VCPKG_BUILD_TYPE is set to release or debug

[ras0219-msft]

Awesome, thanks for the PR!