cifs: hide unused functions

The newly added SMB2+ attribute support causes unused function
warnings when CONFIG_CIFS_XATTR is disabled:

fs/cifs/smb2ops.c:563:1: error: 'smb2_set_ea' defined but not used [-Werror=unused-function]
 smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
fs/cifs/smb2ops.c:513:1: error: 'smb2_query_eas' defined but not used [-Werror=unused-function]
 smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,

This adds another #ifdef around the affected functions.

Fixes: 5517554e ("cifs: Add support for writing attributes on SMB2+")
Fixes: 95907fea ("cifs: Add support for reading attributes on SMB2+")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Steve French <smfrench@gmail.com>

fs/cifs/smb2ops.c

@@ -426,6 +426,7 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
 	return rc;
 }
 
+#ifdef CONFIG_CIFS_XATTR
 static ssize_t
 move_smb2_ea_to_cifs(char *dst, size_t dst_size,
 		     struct smb2_file_full_ea_info *src, size_t src_size,
@@ -613,6 +614,7 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
 
 	return rc;
 }
+#endif
 
 static bool
 smb2_can_echo(struct TCP_Server_Info *server)