!1693 nvme-pci: fix mempool alloc size

Merge Pull Request from: @ci-robot 
 
PR sync from: Yong Hu <yong.hu@windriver.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/XTDSXHQRPNWUUNE6Y2PWP2E3MPZWCWPC/ 
 
https://gitee.com/openeuler/kernel/issues/I7PZZC 
 
Link:https://gitee.com/openeuler/kernel/pulls/1693

 

Reviewed-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>