ChunkFile: Provide additional helpers for C-style arrays

Gets rid of magic numbers in cases where the array size is known at compile time.
This is also useful for future entries that are stack allocated arrays as these
functions prevent incorrect sizes being provided.

Source/Core/VideoCommon/VideoState.cpp

@@ -31,7 +31,7 @@ static void DoState(PointerWrap &p)
 	p.DoMarker("XF Memory");
 
 	// Texture decoder
-	p.DoArray(texMem, TMEM_SIZE);
+	p.DoArray(texMem);
 	p.DoMarker("texMem");
 
 	// FIFO