Description of problem:
a non-priv user can not create a VM if 'all-namespaces' is selected as namespace.

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

How reproducible:
100%

Steps to Reproduce:
1. login as non-priv user and navigate to Virtualization -> Catalog
2. select any template (make sure no namespace is selected)
3. click on "Customize VirtualMachine"
4. click on "Review and create Virtual Machine"
5. get following error:
Create VirtualMachine error
processedtemplates.template.openshift.io is forbidden: User "test" cannot create resource "processedtemplates" in API group "template.openshift.io" in the namespace "default"

Actual results:
since no namespace was selected, we assign the namespace "default" to our process request, as non-priv user has no permission to process a template in that namespace we fail

Expected results:
we want to alert the user that there is no namespace selected, and should not allowed to continue with the create VM process

Additional info: