ksmbd: use ksmbd_req_buf_next() in ksmbd_verify_smb_message()

mainline inclusion
from mainline-5.16-rc1
commit a088ac85
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I60T7G
CVE: NA

Reference: https://git.kernel.org/torvalds/linux/c/a088ac859f81



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Use ksmbd_req_buf_next() in ksmbd_verify_smb_message().

Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Ralph Boehme <slow@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Zhong Jinghua <zhongjinghua@huawei.com>