RDMA/rtrs-clt: Use this_cpu_ API for stats

Use this_cpu_x() for increasing/adding a percpu counter through a
percpu pointer without the need to disable/enable preemption.

Link: https://lore.kernel.org/r/20220712103113.617754-3-haris.iqbal@ionos.com


Suggested-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Santosh Kumar Pradhan <santosh.pradhan@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Reviewed-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>