prevent kernel address space leak via dmesg or /proc files
Enable runtime sysctl hardening in order to avoid kernel
addresses being disclosed via dmesg (in case it was built
in without restrictions) or various /proc files.
See https://kernsec.org/wiki/index.php/Kernel_Self_Protection_Project/Recommended_Settings
for further information.
Signed-off-by: Peter Müller <peter.mueller@ipfire.org> Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>