Fix ServiceTypes, ExcludeServiceTypes, and DocPath desktop file entries to match XDG specifications

diff --git a/smb4k/smb4k.desktop b/smb4k/smb4k.desktop
index 3cc9570..88656d0 100644
--- a/smb4k/smb4k.desktop
+++ b/smb4k/smb4k.desktop
@@ -73,7 +73,7 @@
 Comment[zh_CN]=SMB ���������������
 Exec=smb4k
 Icon=smb4k
-DocPath=smb4k/index.html
+X-DocPath=smb4k/index.html
 Type=Application
 Terminal=false
 Categories=Qt;TDE;Network;