Backend: Fix bug build with clang
Backend: Fix bug build with clang

When using clang template name can not be the same with class variable.
This bug will cause the gen ir load/store switch and casue self test
error.

Signed-off-by: Pan Xiuli <e5a665b1e626c5dc0826076a8b5a209eb48bf6ee@intel.com>
Reviewed-by: Yang Rong <78759e37dc7114caed18f74e7515c5cb519dbf6d@intel.com>

wdv4758h/beignet,wdv4758h/beignet,wdv4758h/beignet,wdv4758h/beignet,wdv4758h/beignet