RDMA/qedr: clean up work queue on failure in qedr_alloc_resources()

[ Upstream commit 7a47e077 ]

Add a check for if create_singlethread_workqueue() fails and also destroy
the work queue on failure paths.

Fixes: e411e058

 ("RDMA/qedr: Add iWARP connection management functions")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/Y1gBkDucQhhWj5YM@kili
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>