[platform-detection] isROSAHCP boolean flag in platform struct needs to be rethought

[ezio-auditore]

With this #2465 a temporary change has been introduced in the platform struct - isROSAHCP boolean flag.
This will cause more such flags to come into the picture for other such platforms like OpenShift, HCP, OSD, ROSA_CLASSIC, ROSA_HCP, ARO.
This approach needs to be discussed and rethought