ksmbd: fix typo, syncronous->synchronous

mainline inclusion
from mainline-v6.3-rc1
commit f8d6e744
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6KEWO?from=project-issue
CVE: CVE-2023-1193

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f8d6e7442aa716a233c7eba99dec628f8885e00b



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syncronous->synchronous

Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>