Description of problem:

In HCP cluster wizard, if the user tries to add a machine pools with autoscaling enabled and mention the maximum node count value exceeds the support limit count then there was no field validation thrown. The Submission action fails with backend error. This was seen with "Add machine pool" dialog.
Ex: Sum total of machine pool node count in cluster is Min: 4 Max: 7 with auto-scaling enabled. But user allowed to set the node count as 50 which is wrong and no validation in place. The maximum node count supported in this case should be 51 - 7 = 44

see the recording attached AddMachinePoolWrongCountCalculation.mp4

How reproducible:

always

Steps to Reproduce:

1. Launch OCM UI staging.
2. Go to a ready ROSA HCP cluster.
3. Go to machine pool tab.
4. Click "Add machine pool" button.
5. Set the maximum nodes to 50. (or <51 and > 51-N where N will be sum of node count across all machine pool)
6. Click "Add machine pool" button.
7. See the behavior.

Actual results:

There was no validation error thrown against the maximum node count field when the specified count greater than supported limits. The error reported from backend when submitting the machine pool data.

Expected results:
Do not show unsupported node count values in compute node count definitions. 

Throw validation error against maximum node count when the limit exceeds the allowed limit.