RDMA/bnxt_re: Add a check for memory allocation

RDMA/bnxt_re: Add a check for memory allocation

__alloc_pbl() can return error when memory allocation fails.
Driver is not checking the status on one of the instances.

Fixes: 0c4dcd602817 ("RDMA/bnxt_re: Refactor hardware queue memory allocation")
Link: https://patch.msgid.link/r/1726715161-18941-4-git-send-email-selvin.xavier@broadcom.com
Reviewed-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>