Revert "fix(migtd/migration): restrict GetTDReport to emulation builds"

[sgrams]

This reverts commit 7b98d80.

[jyao1]

For 7b98d80, I think we should NOT blindly disable the interface and block the VMM get a fresh TDReport for further evaluation.
I feel the fix could to change the final REPORTDATA_final = Math (NONCE_vmm_input), e.g. REPORTDATA_final = "VmmInputToMigTd" || SHA384("VmmInputToMigTdForHash" || NONCE_input), to make sure the VMM cannot input arbitrary REPORTDATA, while VMM can still input something to verify the freshness.
@haitaohuang , please let us know if the direction is OK.

[haitaohuang]

Thanks @jyao1 that should work for us. Please ensure the final fix also address the original security issue triggered the disabling.

[jyao1]

It seems there is no requirement to have a VMM input NONCE.
As such, the simple fix is to just use a fixed string as REPORTDATA = "HostRequestedMigTDReport".

@haitaohuang , please confirm if that is OK.

[haitaohuang]

@jyao1 Yes, confirmed no requirement for VMM to input Nonce. Thanks

[sgrams]

I'll prepare a follow up commit

[sgrams]

@jyao1, @haitaohuang please see and review the follow-up fix commit

[haitaohuang]

LGTM
Thanks