[materialx] Fix usage error

[jimwang118]

Fix the following error:

CMake Error at E:/usd/installed/x64-windows/share/MaterialX/MaterialXConfig.cmake:19 (message):
  File or directory E:/usd/installed/x64-windows/resources referenced by
  variable MATERIALX_RESOURCES_DIR does not exist !

Disable the MATERIALX_BUILD_RENDER property to not compile MaterialX Render modules.

• Changes comply with the maintainer guide.
• SHA512s are updated for each updated download.
• The "supports" clause reflects platforms that may be fixed by this new version.
• Any fixed CI baseline entries are removed from that file.
• Any patches that are no longer applied are deleted from the port's directory.
• The version database is fixed by rerunning ./vcpkg x-add-version --all and committing the result.
• Only one version is added to each modified port's versions file.

Usage test passed with x64-windows triplet.

[dg0yt]

Okay...
First the resources are installed by the package.
Then the installed resources are removed by the portfile.
Then the usage fails.
Then vcpkg maintainers decide "to not compile MaterialX Render modules". 😕

[jimwang118]

Okay... First the resources are installed by the package. Then the installed resources are removed by the portfile. Then the usage fails. Then vcpkg maintainers decide "to not compile MaterialX Render modules". 😕

The error fix has been deleted and re-applied.