RDMA/erdma: Fix opcode conditional check

RDMA/erdma: Fix opcode conditional check

Fix conditional if else check by checking with wr->opcode.
The indicated dead code may have performed some action; that
action will never occur as op is pre-assigned a different value.

Fixes: 999a0a2e9b87 ("RDMA/erdma: Support UD QPs and UD WRs")
Signed-off-by: Advait Dhamorikar <advaitdhamorikar@gmail.com>
Link: https://patch.msgid.link/20241219043939.10344-1-advaitdhamorikar@gmail.com
Reviewed-by: Cheng Xu <chengyou@linux.alibaba.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>