license: GPL-2.0-only repo-wide

Replaces the dual MIT/Apache-2.0 licensing (and its GPL carve-out) with a
single GPL-2.0-only license for the whole repository: coherent with the
kernel patch series it exists to carry, the embedded-Linux norm, and the
stack's openness principle — anyone shipping products on this SDK publishes
their changes. GPL-2.0 (not 3) deliberately: the Installation-Information
clause of GPLv3 sits badly with WardenOS's signed A/B firmware chain.
LICENSE is now the canonical GPLv2 text; crate manifests updated;
inbound = outbound noted in the README.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018HUayid7W5w7jBdb9Rrj1K

patches/README.md

@@ -31,9 +31,8 @@ with `../build/warden_defconfig` → `zImage` + `rv1106-warden.dtb`).
 
 Everything in this directory is a derivative work of the Linux kernel and of
 GPL-2.0 vendor kernel code: **GPL-2.0-only** (or the per-file SPDX identifier
-where one is present), regardless of the MIT/Apache dual license the rest of
-the repository uses. See the top-level `LICENSE` and
-`kernel/rv1106-enablement/PROVENANCE.md` (per-driver origin + license).
+where one is present), the same license the whole repository carries. Per-driver
+origin and license are tracked in `kernel/rv1106-enablement/PROVENANCE.md`.
 
 ## Provenance & regeneration