NetworkPkg: Update NetworkPkg.uni to UTF-8 file format

NetworkPkg: Update NetworkPkg.uni to UTF-8 file format

Patch "NetworkPkg: Update iSCSI driver to check existing AIP instances"
updates NetworkPkg.uni to UTF-16LE wrongly. The patch uses
BaseTools\Scripts\ConvertUni.py to change it back to UTF-8 file format.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ye Ting <ting.ye@intel.com>
Reviewed-by: Gao Liming <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19483 6f19259b-4bc3-4df7-8a09-765794883524