linux: Give CONFIG_RANDOMIZE_BASE on aarch64 another try

linux: Give CONFIG_RANDOMIZE_BASE on aarch64 another try

Quoted from https://capsule8.com/blog/kernel-configuration-glossary/:

> Significance: Critical
>
> In support of Kernel Address Space Layout Randomization (KASLR) this randomizes
> the physical address at which the kernel image is decompressed and the virtual
> address where the kernel image is mapped as a security feature that deters
> exploit attempts relying on knowledge of the location of kernel code internals.

We tried to enable this back in 2020, and failed. Since then, things
may have been improved, so let's give this low-hanging fruit another
try.

Fixes: #12363
Signed-off-by: Peter Müller <peter.mueller@ipfire.org>