RDMA/hfi: Replace cpumask_weight with cpumask_empty where appropriate

drivers/infiniband/hw/hfi1/affinity.c code calls cpumask_weight() to check
if any bit of a given cpumask is set. We can do it more efficiently with
cpumask_empty() because cpumask_empty() stops traversing the cpumask as
soon as it finds first set bit, while cpumask_weight() counts all bits
unconditionally.

Link: https://lore.kernel.org/r/20220210224933.379149-20-yury.norov@gmail.com


Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>