Minor update to build.bat.
Minor update to build.bat.

qiuwch/unrealcv,unrealcv/unrealcv,qiuwch/unrealcv,qiuwch/unrealcv,unrealcv/unrealcv,unrealcv/unrealcv,qiuwch/unrealcv,qiuwch/unrealcv,unrealcv/unrealcv,qiuwch/unrealcv,unrealcv/unrealcv