RDMA/irdma: Do not generate SW completions for NOPs

Currently, artificial SW completions are generated for NOP wqes which can
generate unexpected completions with wr_id = 0. Skip the generation of
artificial completions for NOPs.

Fixes: 81091d76

 ("RDMA/irdma: Add SW mechanism to generate completions on error")
Signed-off-by: Mustafa Ismail <mustafa.ismail@intel.com>
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Link: https://lore.kernel.org/r/20230315145231.931-2-shiraz.saleem@intel.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>