Remove unused CPack build config from package names

Adopt LegalizeAdulthood's CPack package name cleanup from open-simh PR
537. The `CPACK_BUILD_CONFIG` variable is not a predefined CMake or
CPack variable and is not set by this tree.

Author: pmetzger

cmake/cpack-setup.cmake

@@ -39,7 +39,6 @@ else ()
             list(APPEND buildSuffix "win32")
         endif ()
 
-        list(APPEND buildSuffix "\${CPACK_BUILD_CONFIG}")
         ## If using Visual Studio, append the compiler and toolkit:
         if (CMAKE_GENERATOR MATCHES "Visual Studio 17 .*")
             list(APPEND buildSuffix "vs2022")