cmake: avoid warning of missing include dir

cmake/CMakeLists.txt

@@ -414,6 +414,7 @@ if(PKG_MSCG)
     set(MSCG_INCLUDE_DIRS ${SOURCE_DIR}/src)
     list(APPEND LAMMPS_DEPS mscg_build)
     if(NOT LAPACK_FOUND)
+      file(MAKE_DIRECTORY ${MSCG_INCLUDE_DIRS})
       add_dependencies(mscg_build linalg)
     endif()
   else()