fix bin/cl-program-tester tests/cl/program/execute/attributes.cl regression.
fix bin/cl-program-tester tests/cl/program/execute/attributes.cl regression.

work_group_size_hint should define another variable.

Signed-off-by: Luo Xionghu <c3dafbeb50547b880155fb36e6f40d38b44f6611@intel.com>
Reviewed-by: Zhigang Gong <e04a7b9b70b1e4c6318cf117dcd1a9056e14b97a@linux.intel.com>

freedesktop-unofficial-mirror/beignet,wdv4758h/beignet,zhenyw/beignet,wdv4758h/beignet,freedesktop-unofficial-mirror/beignet,zhenyw/beignet,freedesktop-unofficial-mirror/beignet,freedesktop-unofficial-mirror/beignet,zhenyw/beignet,zhenyw/beignet,zhenyw/beignet,wdv4758h/beignet,wdv4758h/beignet,wdv4758h/beignet