#0: Sanitize writes to mailbox on ethernet cores.

[jbaumanTT]

Problem description

The NOC may be used to write data to the mailbox on ethernet cores, causing later programs to fail to launch.

What's changed

Modify the sanitizer to check that the mailbox isn't being written to directly on ethernet cores (outside the dispatcher, which is allowed to do that).

Checklist

• Post commit CI passes
• Blackhole Post commit (if applicable)
• Model regression CI testing passes (if applicable)
• Device performance regression CI testing passes (if applicable)
• (For models and ops writers) Full new models tests passes
• New/Existing tests provide coverage for changes