vulkan/opengl: fix reported texture memory usage of texture views.

src/modules/graphics/opengl/Texture.cpp

@@ -440,6 +440,7 @@ bool Texture::loadVolatile()
 		}
 	}
 
+	if (parentView.texture == this)
 		updateGraphicsMemorySize(true);
 
 	return true;

src/modules/graphics/vulkan/Texture.cpp

@@ -286,6 +286,7 @@ bool Texture::loadVolatile()
 		}
 	}
 
+	if (root)
 		updateGraphicsMemorySize(true);
 
 	return true;