MdeModulePkg: Add DNS QType and QClass values definition

This patch is used to add DNS QType and QClass values definition
in NetLib.h

Cc: Hegde Nagaraj P <nagaraj-p.hegde@hpe.com>
Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiaxin Wu <jiaxin.wu@intel.com>
Reviewed-by: Hegde Nagaraj P <nagaraj-p.hegde@hpe.com>
Reviewed-by: Ye Ting <ting.ye@intel.com>
Reviewed-by: Fu Siyuan <siyuan.fu@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19642 6f19259b-4bc3-4df7-8a09-765794883524