NetworkPkg: Fix DNS GeneralLookUp failure in some case

NetworkPkg: Fix DNS GeneralLookUp failure in some case

QClass value may be not equal to 1(DNS_CLASS_INET) when
GeneralLookUp query is called. So, remove QClass value check.
Moreover, the 'Identification' and 'Type' filed in Query packet
should not be changed to little endian since the packet maybe
retransmitted while there is any error happened.

Cc: Ye Ting <ting.ye@intel.com>
Cc: Zhang Lubo <lubo.zhang@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiaxin Wu <jiaxin.wu@intel.com>
Reviewed-by: Ye Ting <ting.ye@intel.com>
Reviewed-by: Zhang Lubo <lubo.zhang@intel.com>