fix: caddy cannot accept connections

[mzz2017]

Background

Caddy and samba cannot work.

This may be some special use of their listening socket, because bpf_assign returns -94 (ESOCKTNOSUPPORT).

This problem is NOT about PSH flag of TCP.

This is most likely because the caddy port has enabled IP_TRANSPARENT sockopt.

Checklist

• The Pull Request has been fully tested
• There's an entry in the CHANGELOGS
• There is a user-facing docs PR against https://github.com/daeuniverse/dae

Full changelogs

• Just accept the skb once bpf_assign returns -94 (ESOCKTNOSUPPORT).
• Deprecate CFLAGS -D__REMOVE_BPF_PRINTK

Issue reference

Closes #261. Related #154.

Test Result

[dae-prow]

❌ Your branch is currently out-of-sync to main. No worry, I will fix it for you.

[mzz2017]

Test Result:

[dae-prow]

🧪 Since the PR has been fully tested, please consider merging it.