RDMA/rxe: Replace WR_REG_MASK by WR_LOCAL_OP_MASK

Rxe has two mask bits WR_LOCAL_MASK and WR_REG_MASK with WR_REG_MASK used
to indicate any local operation and WR_LOCAL_MASK unused. This patch
replaces both of these with one mask bit WR_LOCAL_OP_MASK which is
clearer.

Link: https://lore.kernel.org/r/20210608042552.33275-6-rpearsonhpe@gmail.com


Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>