FindLua: only mark LUA_MATH_LIBRARY as advanced if required

Modules/FindLua.cmake

@@ -211,6 +211,7 @@ if (LUA_LIBRARY)
   # include the math library for Unix
   if (UNIX AND NOT APPLE AND NOT BEOS)
     find_library(LUA_MATH_LIBRARY m)
+    mark_as_advanced(LUA_MATH_LIBRARY)
     set(LUA_LIBRARIES "${LUA_LIBRARY};${LUA_MATH_LIBRARY}")
 
     # include dl library for statically-linked Lua library
@@ -232,6 +233,6 @@ FIND_PACKAGE_HANDLE_STANDARD_ARGS(Lua
                                   REQUIRED_VARS LUA_LIBRARIES LUA_INCLUDE_DIR
                                   VERSION_VAR LUA_VERSION_STRING)
 
-mark_as_advanced(LUA_INCLUDE_DIR LUA_LIBRARY LUA_MATH_LIBRARY)
+mark_as_advanced(LUA_INCLUDE_DIR LUA_LIBRARY)
 
 cmake_policy(POP)