make_element: fix replacing regarding class name of template
Since 'commit 581abbd4 "Use G_DECLARE_FINAL_TYPE()"' the replace method fails because 'GST_PLUGIN_TEMPLATE' no longer exists. This fix solves the following compile problem.
undefined reference to `GST_TESTPLUGIN'
Signed-off-by: Silvio Fricke silvio.fricke@gmail.com
Edited by Tim-Philipp Müller