Outdated README links/code

### This issue is for a: (mark with an `x`)
```
- [ ] bug report -> please search issues before submitting
- [ ] feature request
- [x] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
```

### Mention any other details that might be useful

It appears that the `sgx.attest.sample.intel.sdk` readme references both files and code that no longer exist under the `Remote Quote Validation via MAA Attestation` heading. A similar case exists for the `sgx.attest.sample.oe.sdk` readme.

Locate the README files for sgx.attest.sample.intel.sdk and sgx.attest.sample.oe.sdk, then read the “Remote Quote Validation via MAA Attestation” sections. Check which referenced files and code no longer exist, and confirm the documentation contains only current references when done.

Written by the indexing model from the issue text.