Tweak kernel config after update

[pothos]

Current situation

The Linux 6.1 kernel update brought some unexpected changes which could also be related to the increased size.

Impact

The unpriv ebpf setting changed. The kernel is maybe larger than needed?

Ideal future situation

No regression in behavior/features, no new features unless wanted.

Implementation options

Additional information

• unpriv ebpf: sys-kernel/*: Bump to kernel 6.1.27 scripts#810 (comment)
• USELIB: sys-kernel/*: Bump to kernel 6.1.27 scripts#810 (comment)
  but in general we have to review most settings again since it wasn't really done for long time - e.g., we are missing out on some interesting stuff and hardware support [RFE] Review kernel config to enable new features #855 but on the other hand, the size limit is almost hit Reduce vmlinuz size #688 (approaches like CONFIG_EFI_ZBOOT could help for arm64 but my hope is that a review would identify things that we don't really need)