package/smartmontools: fix build without stack-protector

Fixes:
 - http://autobuild.buildroot.org/results/0de9f2a69fa2a39164211299f8a429d2fec6935a



Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>