[BUG] CMake plugin generate invalid target name for header only package

with CMP00037 ON ( default ) error is : 
```
  The target name "boost_config::boost_config" is reserved or not valid for
  certain CMake features, such as generator expressions, and may result in
  undefined behavior.
``` 

with  cmake_policy(SET CMP0037 OLD) error is :
```
  add_library Invalid name for INTERFACE library target:
  boost_config::boost_config
```
