Enable CONFIG_SECURITY_LANDLOCK for RHEL

Landlock allows unprivileged user processes to build security sandboxes. It is used by various user-space programs so it's beneficial to enable it also for RHEL users.

7ef47bf8 enabled Landlock for Fedora in 2011. 4ef65026 moved CONFIG_SECURITY_PATH to common. This commit enables Landlock also for RHEL.

Requested by Mickaël Salaün mic@digikod.net during LPC this year.

Signed-off-by: Zbigniew Jędrzejewski-Szmek zbyszek@in.waw.pl