We don't need them in libcompel for PIE - only needed for C/R.

Fixes (with compat enabled back):
  CC       criu/arch/x86/sigaction_compat.o
In file included from criu/arch/x86/sigaction_compat.c:1:0:
/home/japdoll/tools/criu/criu/arch/x86/include/asm/restorer.h:15:25: error: unknown type name ‘tls_t’
 extern void restore_tls(tls_t *ptls);
                         ^~~~~

travis-ci: success for Compel/compat cleanups
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>