Different link for Identity Provider for MFA authentication

##### ISSUE TYPE

* Improvement Request

##### COMPONENT NAME

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Core
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##### CLOUDSTACK VERSION

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4.17.2
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##### CONFIGURATION

It would be great to have the possibility of customizing the FQDN of identity provider link per domain for MFA.
We don't need to have multiple platforms connected to CS, just to have the possibility of configure a sort of cname.

For example: for "Society one" having authentication.societyone.com and for "Society two" having authentication.societytwo.com

##### OS / ENVIRONMENT

CentOS 7

##### SUMMARY

##### STEPS TO REPRODUCE

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##### EXPECTED RESULTS

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##### ACTUAL RESULTS

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It is not possible actually to have a different link for MFA
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Comece localizando o tratamento dos links do provedor de identidade MFA do CloudStack e seu ponto de entrada de configuração de domínio. Defina como os valores FQDN ou CNAME por domínio devem ser configurados e verifique se cada domínio produz seu link MFA pretendido; a issue não menciona testes nem arquivos.

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