Kernel: Make clang(?) happy about templates(?)

This caused some issues with QtCreator, and since it's not wrong and improves
readability very slightly, I adopt it.

Kernel/Random.h

@@ -46,9 +46,9 @@ public:
     constexpr static size_t reseed_threshold = 16;
 
     using CipherType = CipherT;
-    using BlockType = CipherT::BlockType;
+    using BlockType = typename CipherT::BlockType;
     using HashType = HashT;
-    using DigestType = HashT::DigestType;
+    using DigestType = typename HashT::DigestType;
 
     FortunaPRNG()
         : m_counter(ByteBuffer::create_zeroed(BlockType::block_size()))