IB/ipath: Fix UC receive completion opcode for RDMA WRITE with immediate

When I fixed the RC receive completion opcode in 2bfc8e9e

 ("IB/ipath:
Return the correct opcode for RDMA WRITE with immediate"), I forgot to
fix UC, which had the same problem for RDMA write with immediate
returning the wrong opcode.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>