qbs build: Support new variable QTCREATOR_COPYRIGHT_YEAR

Change-Id: I2b5ca4f93456857b0c4ac8b7960982b28f5f0761
Reviewed-by: Kai Koehne <kai.koehne@qt.io>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

qbs/modules/pluginjson/pluginjson.qbs

@@ -54,6 +54,8 @@ Module {
                 vars['IDE_VERSION_MAJOR'] = product.moduleProperty("qtc", "ide_version_major");
                 vars['IDE_VERSION_MINOR'] = product.moduleProperty("qtc", "ide_version_minor");
                 vars['IDE_VERSION_RELEASE'] = product.moduleProperty("qtc", "ide_version_release");
+                vars['QTCREATOR_COPYRIGHT_YEAR']
+                        = product.moduleProperty("qtc", "qtcreator_copyright_year")
                 var deplist = [];
                 for (i in plugin_depends) {
                     deplist.push("        { \"Name\" : \"" + plugin_depends[i] + "\", \"Version\" : \"" + qtcVersion + "\" }");