09cda9d5 Allow imported INTERFACE libraries to specify a link library name
1d1f1eeb cmTarget: Refactor GetMappedConfig to choose location property up front
479932fa cmTarget: Add comment clarifying interface library special case
925e4270 cmTarget: Clarify comments in GetMappedConfig
Add an `IMPORTED_LIBNAME[_<CONFIG>]` target property to specify a library
name to be placed on the link line in place of an interface library
since it has no library file of its own. Restrict use of the property
to imported `INTERFACE` libraries.
This will be particularly useful for find modules that need to provide
imported libraries from system SDKs where the full path to the library
file is not known. Now such find modules will be able to provide an
imported interface library and set `IMPORTED_LIBNAME` to refer to the
SDK library by name.
Issue: #15267