external: drop armhf where upstream no longer builds it

[igorpecovnik]

Four external/*.conf sources still ask for armhf from upstreams that stopped producing it. Both were found by diffing what every armhf job in run 35467743134 actually kept against its arm64 counterpart.

codium — no armhf asset at all

VSCodium publishes nothing matching any armhf pattern. All five releases warn_skip every night and upload nothing:

skipping codium bookworm/armhf: no .deb matched for arch armhf
  (repo https://github.com/VSCodium/vscodium,
   patterns: *armhf*.deb *armv7*.deb *armv7l*.deb *armv6*.deb)

Same on forky, noble, resolute, trixie. The arm64 jobs have no such warning.

chromium-{jammy,noble,resolute} — armhf frozen upstream

xtradeb stopped publishing armhf, so the mirror is pinned to an abandoned build 3–4 major Chrome versions behind arm64:

release	arm64	armhf
jammy	153.0.8010.52	149.0.7827.114
noble	153.0.8010.52	150.0.7871.181
resolute	153.0.8010.52	149.0.7827.196

The arch-independent components in the same armhf job (chromium-l10n) are at 153, which is what distinguishes a frozen architecture from one that is merely lagging.

Everything else armhf is current and untouched

Every other armhf source in the matrix was compared against its arm64 counterpart and comes back version-identical: firefox-*, thunderbird-*, widevine-noble, zfs-*, harfbuzz-jammy, libcec6-sid-to-jammy, gnome-packagekit-to-trixie, and all twelve rpi-* sources. The gh-method ones pull real armv7 assets (min-1.35.7-armv7l.deb, fastfetch-linux-armv7l.deb, and the gh/haos-agent armv6/armv7 debs).

code looked suspicious — armhf 1.138.0-1789458517 vs arm64 1.138.0-1789458676 — but that is only Microsoft's per-arch build id against the same upstream 1.138.0, so it stays.

Effect

8 fewer jobs per run (5 codium + 3 chromium) and roughly 725 MiB less downloaded, on top of what armbian/armbian.github.io#463 already saves.

Deliberately not included

The stale armhf chromium already published in the repository is not removed here; it needs a separate PURGE pass and is being left in place for now. Neither package appears in any desktop package list in armbian/build, so no image build depends on either.