ksmbd: fix memory leak in ksmbd_vfs_get_sd_xattr()

mainline inclusion
from mainline-5.15-rc1
commit 78ad2c27
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I60T7G
CVE: NA

Reference: https://git.kernel.org/torvalds/linux/c/78ad2c277af4



-------------------------------

Add free acl.sd_buf and n.data on error handling in
ksmbd_vfs_get_sd_xattr().

Reported-by: Coverity Scan <scan-admin@coverity.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Zhong Jinghua <zhongjinghua@huawei.com>