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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Inizia individuando la gestione dei link del provider di identità MFA di CloudStack e il relativo punto di ingresso per la configurazione dei domini. Definisci come devono essere configurati i valori FQDN o CNAME per ciascun dominio e verifica che ogni dominio produca il link MFA previsto; l’issue non indica test o file.

Scritto dal modello di indicizzazione a partire dal testo della issue.