xfs: use strscpy() to instead of strncpy()

The implementation of strscpy() is more robust and safer.
That's now the recommended way to copy NUL-terminated strings.
Signed-off-by: NXu Panda <xu.panda@zte.com.cn>
Signed-off-by: NYang Yang <yang.yang29@zte.com.cn>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

fs/xfs/xfs_xattr.c

@@ -212,9 +212,7 @@ __xfs_xattr_put_listent(
 	offset = context->buffer + context->count;
 	memcpy(offset, prefix, prefix_len);
 	offset += prefix_len;
-	strncpy(offset, (char *)name, namelen);			/* real name */
-	offset += namelen;
-	*offset = '\0';
+	strscpy(offset, (char *)name, namelen + 1);			/* real name */
 
 compute_size:
 	context->count += prefix_len + namelen + 1;