BaseTools/UPT: Replace os.linesep with '\r\n' when generating UNI files.

BaseTools/UPT: Replace os.linesep with '\r\n' when generating UNI files.

Replace os.linesep with '\r\n' when generating UNI files to make sure all files are under DOS format.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hess Chen <hesheng.chen@intel.com>
Reviewed-by: Gao, Liming <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16041 6f19259b-4bc3-4df7-8a09-765794883524