Description of problem: As a VM owner, I want to add a disk to a VM by uploading a disk from my local machine

Version-Release number of selected component (if applicable): 4.10.0

How reproducible: Always

Steps to Reproduce:
1. Enter create VM wizard
2. Select a template with an existing boot source
3. Customize VM
4. In storage section, Add disk

Actual results: No option exists to upload a disk

Expected results: An option to upload a disk is present

Additional info: