embed a VERSIONINFO resource into Qt plugins

This reverts f0ee55c00. VERSION actually makes sense on Windows,
because it embeds a VERSIONINFO resource into the DLL that can
be inspected by the user.

Task-number: QTBUG-37961
Change-Id: I6b81b5aa999eba16cb8d9a4d61bd596310af46b9
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>

mkspecs/features/qt_plugin.prf

@@ -17,6 +17,12 @@ TEMPLATE = lib
 CONFIG += plugin
 DESTDIR = $$MODULE_BASE_OUTDIR/plugins/$$PLUGIN_TYPE
 
+win32:CONFIG(shared, static|shared) {
+    # Embed a VERSIONINFO resource into the plugin's DLL.
+    isEmpty(VERSION): VERSION = $$QT_VERSION
+    CONFIG += skip_target_version_ext
+}
+
 tool_plugin {
     !build_pass:contains(QT_CONFIG, build_all): CONFIG += release
 } else:if(win32|mac):!macx-xcode {