fix for depending Makefile projects: do not add -l option to full-path library names

cmake/create_cmake_config_files.cmake

@@ -32,7 +32,11 @@ endforeach()
 
 string(REPLACE " " ";" LIST ${${PROJECT_NAME}_LIBRARIES})
 foreach(LIBRARY ${LIST})
-  set(${PROJECT_NAME}_LINKER_FLAGS_MAKEFILE "${${PROJECT_NAME}_LINKER_FLAGS_MAKEFILE} -l${LIBRARY}")
+  if(LIBRARY MATCHES "/")  # library name contains slashes: link against the a file path name
+    set(${PROJECT_NAME}_LINKER_FLAGS_MAKEFILE "${${PROJECT_NAME}_LINKER_FLAGS_MAKEFILE} ${LIBRARY}")
+  else()                   # library name does not contain slashes: link against library with -l option
+    set(${PROJECT_NAME}_LINKER_FLAGS_MAKEFILE "${${PROJECT_NAME}_LINKER_FLAGS_MAKEFILE} -l${LIBRARY}")
+  endif()
 endforeach()
 
 # we have nested @-statements, so we have to parse twice: