s390x: TestSimKeyCreateAndLoad: SIGILL: illegal instruction PC=0xdcb8f423b4798b m=0 sigcode=2 signal arrived during cgo execution instruction bytes:signal: segmentation fault

Hi! I help maintain this package in Debian, and when upgrading from v0.6.0 to v0.6.1 we got a build failure on s390x.

https://buildd.debian.org/status/fetch.php?pkg=golang-github-google-go-attestation&arch=s390x&ver=0.6.1-1&stamp=1785448691&raw=0

Any ideas? Could this be a Go compiler/runtime issue? Or do the go-attestation code do some low-level cgo stuff that could indicate the bug is within this package?

Go version is 1.26.5 as can be seen in build logs.

Thanks,
Simon

```
=== RUN TestSimKeyCreateAndLoad
SIGILL: illegal instruction
PC=0xdcb8f423b4798b m=0 sigcode=2
signal arrived during cgo execution
instruction bytes:signal: segmentation fault
FAIL github.com/google/go-attestation/attest 0.007s
? github.com/google/go-attestation/attest/attest-tool [no test files]
? github.com/google/go-attestation/attest/attest-tool/internal [no test files]
```

Reproduce attest.TestSimKeyCreateAndLoad on s390x with Go 1.26.5, using the Debian build log as the starting evidence. Inspect the cgo execution path involved in that test and determine whether the SIGILL originates in go-attestation or the Go compiler/runtime. Done means the cause is isolated and the appropriate package or upstream issue is identified.

Written by the indexing model from the issue text.