Add missing const to declaration

glm/detail/type_mat4x4.hpp

@@ -210,7 +210,7 @@ namespace glm
 	GLM_FUNC_DECL typename tmat4x4<T, P>::col_type operator/(tmat4x4<T, P> const & m, typename tmat4x4<T, P>::row_type const & v);
 
 	template <typename T, precision P>
-	GLM_FUNC_DECL typename tmat4x4<T, P>::row_type operator/(typename tmat4x4<T, P>::col_type & v, tmat4x4<T, P> const & m);
+	GLM_FUNC_DECL typename tmat4x4<T, P>::row_type operator/(typename tmat4x4<T, P>::col_type const & v, tmat4x4<T, P> const & m);
 
 	template <typename T, precision P>
 	GLM_FUNC_DECL tmat4x4<T, P> operator/(tmat4x4<T, P> const & m1,	tmat4x4<T, P> const & m2);