RDMA/irdma: Remove excess error variables

As irdma_status_code is replaced with an int, there is no need for two
variables to hold error codes.

Remove the excess variable in functions where this occurs.  Also, remove
any redundant initializations which are no longer needed.

Link: https://lore.kernel.org/r/20220217151851.1518-4-shiraz.saleem@intel.com


Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>