RDMA/irdma: Prevent QP use after free

There is a window where the poll cq may use a QP that has been freed.
This can happen if a CQE is polled before irdma_clean_cqes() can clear the
CQE's related to the QP and the destroy QP races to free the QP memory.
then the QP structures are used in irdma_poll_cq.  Fix this by moving the
clearing of CQE's before the reference is removed and the QP is destroyed.

Fixes: b48c24c2

 ("RDMA/irdma: Implement device supported verb APIs")
Link: https://lore.kernel.org/r/20230522155654.1309-3-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>