GS/OpenGL: Fix incorrect VAO cleanup

This wasn't an issue in wx, since the whole context/device gets torn
down and recreated when you pause/unpause, or change settings.

But on Qt it is, since the context/device is preserved for a
faster/lighter settings apply.

pcsx2/GS/Renderers/OpenGL/GSDeviceOGL.cpp

@@ -103,7 +103,7 @@ GSDeviceOGL::~GSDeviceOGL()
 
 	// Clean vertex buffer state
 	if (m_vertex_array_object)
-		glDeleteVertexArrays(0, &m_vertex_array_object);
+		glDeleteVertexArrays(1, &m_vertex_array_object);
 	m_vertex_stream_buffer.reset();
 	m_index_stream_buffer.reset();