docs: document both firmware sources on equal terms

The repo named WOA-Project as a source and called its cabinets "the easiest
route", while aarch64-laptops appeared only as a place where files "have
circulated before" — despite it having actual .mbn files checked into its tree
and being where the WiFi trio used in today's testing came from. That ranking
was mine, not something the evidence supports.

Both are now documented with what each actually contains. They overlap and
neither is a superset:

WOA-Project is the only source of the two for qcdxkmsuc850.mbn, qcadsp850.mbn,
qccdsp850.mbn, qcslpi850.mbn, qcvss850.mbn and ipa_fws.elf, and publishes nine
versions whose cabinets differ. aarch64-laptops carries the modem/WLAN trio,
the bdwlan board data, a prebuilt board-2.bin and the script that makes it,
a630_gmu.bin, the machine's ACPI tables and a device tree — none of which
WOA-Project has, and it has none of the six above. Its wifi/firmware-5.bin is
an HTML error page rather than firmware, which is worth knowing before copying
it somewhere.

Also restate the modem result without implying a verdict on either source. Both
sets produce the identical QLINK failure here; that shows changing firmware does
not change the outcome, not that either set is wrong, and not that one is more
trustworthy than the other.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XWRjNJMistCy6ngXH5aJLS

README.md

@@ -54,8 +54,9 @@ Note `LIBGL_ALWAYS_SOFTWARE=1` does *not* work here — mutter uses EGL, which
 ignores it.
 
 Getting the firmware: see
-[docs/firmware.md](docs/firmware.md). The cabinets from WOA-Project are the
-easiest route; `sudo c630-firmware` works if the Windows partition survives.
+[docs/firmware.md](docs/firmware.md), which compares the two projects that
+publish it — WOA-Project and aarch64-laptops — and what each one covers.
+`sudo c630-firmware` works if the Windows partition survives.
 
 ## Building