Fix one of https://github.com/microsoft/vcpkg/issues/32398 issue.
```
CMake Error at mariadb_config/CMakeLists.txt:51 (GET_LIB_NAME):
GET_LIB_NAME Function invoked with incorrect arguments for function named:
GET_LIB_NAME
```
Fixed the issue that the search for iconv in Linux did not obtain the
value of the macro variable Iconv_LIBRARIES, causing the function input
parameter check to fail.
- [X] Changes comply with the [maintainer
guide](https://github.com/microsoft/vcpkg-docs/blob/main/vcpkg/contributing/maintainer-guide.md).
- [ ] ~~SHA512s are updated for each updated download.~~
- [ ] ~~The "supports" clause reflects platforms that may be fixed by
this new version.~~
- [ ] ~~Any fixed [CI
baseline](https://github.com/microsoft/vcpkg/blob/master/scripts/ci.baseline.txt)
entries are removed from that file.~~
- [ ] ~~Any patches that are no longer applied are deleted from the
port's directory.~~
- [X] The version database is fixed by rerunning `./vcpkg x-add-version
--all` and committing the result.
- [X] Only one version is added to each modified port's versions file.
Usage test pass with following triplets:
```
x64-linux
```
* Xbox triplets should not support ports with only copyleft licenses
* Reverted ports that build with xbox currently
* Fix conflict and rebase
* Update baseline
* Update baseline
* Update to 3.1.15
* Modernize portfile
* Keep plugins
* Always use vcpkg zlib instead vendored copy
* Use zlib and openssl modules in pc file
* Always install pc file, drop non-relocatable mariadb_config
* UWP is not supported
* Use schannel SSL backend on windows
* Fix exported includedir and libdir
* Fixup windows pc file
* Disable extra static lib
* Disable plugins with extra dependencies
* [libmariadb] Namespace targets with unofficial::
* Update versions
* Enable CI for x86-windows: no conflict with mysql
* Re-enable lib mariadbclient via feature
* Use openssl targets to handle multi-config
* Update versions
* CR request
* Update versions
* [libmariadb] Fix plugin installation, fix pkgconfig
* fix installation
* update version stuff
Co-authored-by: Billy Robert ONeal III <bion@microsoft.com>