cifs: move unix extension call to cifs_query_symlink()

Unix extensions rigth now are only applicable to smb1 operations.
Move the check and subsequent unix extension call to the smb1
specific call to query_symlink() ie. cifs_query_symlink().

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>