Fix compilation on Clang.

src/Magnum/Math/Angle.h

@@ -124,10 +124,10 @@ std::sin(Float(Rad<Float>(b));  // required explicit conversion hints to user
 template<class T> class Deg: public Unit<Deg, T> {
     public:
         /** @brief Construct zero angle */
-        constexpr /*implicit*/ Deg(ZeroInitT = ZeroInit): Unit<Deg, T>{ZeroInit} {}
+        constexpr /*implicit*/ Deg(ZeroInitT = ZeroInit): Unit<Math::Deg, T>{ZeroInit} {}
 
         /** @brief Construct without initializing the contents */
-        explicit Deg(NoInitT): Unit<Deg, T>{NoInit} {}
+        explicit Deg(NoInitT): Unit<Math::Deg, T>{NoInit} {}
 
         /** @brief Explicit constructor from unitless type */
         constexpr explicit Deg(T value): Unit<Math::Deg, T>(value) {}
@@ -185,10 +185,10 @@ See @ref Deg for more information.
 template<class T> class Rad: public Unit<Rad, T> {
     public:
         /** @brief Default constructor */
-        constexpr /*implicit*/ Rad(ZeroInitT = ZeroInit): Unit<Rad, T>{ZeroInit} {}
+        constexpr /*implicit*/ Rad(ZeroInitT = ZeroInit): Unit<Math::Rad, T>{ZeroInit} {}
 
         /** @brief Construct without initializing the contents */
-        explicit Rad(NoInitT): Unit<Rad, T>{NoInit} {}
+        explicit Rad(NoInitT): Unit<Math::Rad, T>{NoInit} {}
 
         /** @brief Construct from unitless type */
         constexpr explicit Rad(T value): Unit<Math::Rad, T>(value) {}