Form conversion: Compute/Infra/PXE/System Image Types Add/Edit

[skateman]

Convert form to use DDF/React and API - parent issue #6825

Location: Compute/Infra/PXE System Image Types
Form: Add new System Image Type
API: None - ManageIQ/manageiq-api#908

[skateman]

@DavidResende0 would you like to try this one? Should be simple and the API endpoint is almost ready