Pass through resource view element size in D3D11 pipeline state

* This lets us calculate the offset and visible length when opening a
  buffer view from a resource binding.

renderdocui/Interop/D3D11PipelineState.cs

@@ -126,6 +126,7 @@ namespace renderdoc
 
                 public bool Structured;
                 public UInt32 BufferStructCount;
+                public UInt32 ElementSize;
 
                 // Buffer (SRV)
                 public UInt32 ElementOffset;