cargo deny: use -only and -or-later suffixes for GPL licenses

The cargo deny command has recently learned these suffixes,
resulting in our current license allowances no longer matching:

     error[rejected]: failed to satisfy license requirements
       ┌─ /home/runner/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/libsystemd-sys-0.9.3/Cargo.toml:22:12
       │
    22 │ license = "LGPL-2.1-or-later WITH GCC-exception-2.0"
       │            ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
       │            │
       │            rejected: license is not explicitly allowed
       │
       ├ LGPL-2.1-or-later - GNU Lesser General Public License v2.1 or later:
       ├   - OSI approved
       ├   - FSF Free/Libre
       ├   - Copyleft
       ├ libsystemd-sys v0.9.3
       └── systemd v0.10.0
           └── tacd v0.2.0

     warning[license-not-encountered]: license was not encountered
       ┌─ /home/runner/work/tacd/tacd/deny.toml:38:6
       │
    38 │     "LGPL-2.1 WITH GCC-exception-2.0",
       │      ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unmatched license allowance

Use the license names with suffixes.

Signed-off-by: Leonard Göhrs <l.goehrs@pengutronix.de>

Author: hnez

deny.toml

@@ -34,8 +34,8 @@ allow = [
     "BSD-2-Clause",
     "BSD-3-Clause",
     "CC0-1.0",
-    "GPL-2.0",
-    "LGPL-2.1 WITH GCC-exception-2.0",
+    "GPL-2.0-only",
+    "LGPL-2.1-or-later WITH GCC-exception-2.0",
     "MIT",
     "Unicode-3.0",
     "Unicode-DFS-2016",