Ignore derived Default implementations during dead code analysis

[mu001999]

Fixes #98871

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[rust-log-analyzer]

The job mingw-check failed! Check out the build log: (web) (plain)

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#13 3.852 Building wheels for collected packages: reuse
#13 3.853   Building wheel for reuse (pyproject.toml): started
#13 4.180   Building wheel for reuse (pyproject.toml): finished with status 'done'
#13 4.181   Created wheel for reuse: filename=reuse-1.1.0-cp310-cp310-manylinux_2_35_x86_64.whl size=181117 sha256=f5f58750481f69515c2c0d1d503daf565e2565c370d07fc6aeb95fe3498b4269
#13 4.181   Stored in directory: /tmp/pip-ephem-wheel-cache-m6mg_29l/wheels/c2/3c/b9/1120c2ab4bd82694f7e6f0537dc5b9a085c13e2c69a8d0c76d
#13 4.184 Installing collected packages: boolean-py, binaryornot, setuptools, reuse, python-debian, markupsafe, license-expression, jinja2, chardet
#13 4.208   Attempting uninstall: setuptools
#13 4.208     Found existing installation: setuptools 59.6.0
#13 4.209     Not uninstalling setuptools at /usr/lib/python3/dist-packages, outside environment /usr
---

error: variant `Init` is never constructed
   --> src/tools/miri/src/shims/tls.rs:229:5
    |
227 | enum TlsDtorsStatePriv {
    |      ----------------- variant in this enum
228 |     #[default]
    |     ^^^^
    |
    |
    = note: `TlsDtorsStatePriv` has derived impls for the traits `Default` and `Debug`, but these are intentionally ignored during dead code analysis
    Checking cargo_metadata v0.15.4
    Checking rustfix v0.6.1
error: could not compile `miri` (lib) due to 2 previous errors
warning: build failed, waiting for other jobs to finish...

[mu001999]

Looks like this doesn't work, we cannot simply add #[rustc_trivial_field_reads].