--layout=versioned breaks FindBoost.cmake

As of the new 1.66 release, it appears that `--layout=versioned` generates the address-model into the library names. This was previously [discussed](https://groups.google.com/forum/#!searchin/boost-developers-archive/dimov$20x64%7Csort:date/boost-developers-archive/G4Bmy_FuBEM/lCKoAf-4BgAJ) on the developers mailinglist.

On Linux, the dynamic link libraries have now the names in the following encoding (the x64 part is new):

> libboost_unit_test_framework-gcc-mt-x64-1_66.so

However, FindBoost.cmake (as of the latest CMake 3.10) is not aware of the x64 part in the library name.

**Questions**: how can I suppress the x64 part using bjam while still using `--layout=versioned`? Or, alternatively, how can I tell CMake to look for a library with x64 in its name?