restore: networking stack files from reflog (Phases 1-6)

Recovered from reflog commits 1c80937e and d0ecc067 after force-push data loss.
Includes: filter/, icmp_error.rs, slaac.rs, bond.rs, bridge.rs, gre.rs, ipip.rs,
qdisc.rs, tun.rs, vlan.rs, vxlan.rs, netfilter.rs, tun.rs, conntrack.rs, nat.rs,
rule.rs, table.rs, redbear-ufw/, dhcpv6d/, netdiag/ — 39 files total.

drivers/graphics/fbcond/src/text.rs

@@ -45,6 +45,10 @@ impl TextScreen {
                             // Backspace
                             buf.extend_from_slice(b"\x7F");
                         }
+                        0x1C => {
+                            // Enter
+                            buf.extend_from_slice(b"\n");
+                        }
                         0x47 => {
                             // Home
                             buf.extend_from_slice(b"\x1B[H");