soc/fsl/qbman: Use for_each_online_cpu() instead of for_each_cpu()

Replace the opencoded for_each_cpu(cpu, cpu_online_mask) loop with the
more readable and equivalent for_each_online_cpu(cpu) macro.

Signed-off-by: Fushuai Wang <wangfushuai@baidu.com>
Link: https://lore.kernel.org/r/20250811065216.3320-1-wangfushuai@baidu.com


Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>