Description of problem:

Create host using compute_profile the 'image' field under 'OS' tab remain disabled and host create failed as well

How reproducible:

Always

Steps to Reproduce:
1. Create CR using AzureRM.
2. Associate compute profile with created CR.
3. Now try to create a host(UI: hosts => Create Host) using this CR and CP .

Actual results:

Under 'Operating system' tab unable to select 'Image' and it by default select any one and this field('Image') shows as disabled.
 hence after submit the create_host same failed with error 'undefined method start_with?'

Expected results:

Should be able to select values under 'Image'

Additional info:

Same has been observed for CR GCE and EC2 as well.