RDMA/irdma: Set VLAN in UD work completion correctly

[ Upstream commit cc07b73e ]

Currently VLAN is reported in UD work completion when VLAN id is zero,
i.e. no VLAN case.

Report VLAN in UD work completion only when VLAN id is non-zero.

Fixes: b48c24c2

 ("RDMA/irdma: Implement device supported verb APIs")
Link: https://lore.kernel.org/r/20211019151654.1943-1-shiraz.saleem@intel.com
Signed-off-by: Mustafa Ismail <mustafa.ismail@intel.com>
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>