[BUG] Virtual BMC's credentials are not respected

[starbops]

Describe the bug

Even though the virtual BMC's username and password are provided in the VirtualMachineBMC CR, there are not respected. Both IPMI and Redfish only work with the default username and password: admin/password. The IPMI service does not even do the authentication. You can provide any credential and still be able to access the IPMI service.

To Reproduce

1. Install KubeVirtBMC chart
2. Create a virtual machine
3. Modify the auto-created VirtualMachineBMC CR, changing its username or password, e.g., from admin/password to demo/secret
4. Query the services with the updated username and password
   • The IPMI service works (because it does not even do the authentication)
   • The Redfish service fails, which is wrong
5. Query the services with the original username and password
   • The IPMI service works, which is wrong
   • The Redfish service works, which is also wrong

Expected behavior

KubeVirtBMC should support custom credentials, not just the default one. The IPMI service should implement the authentication.

Screenshots

N/A

Desktop (please complete the following information):

• OS: Harvester v1.4.0 (based on SLE Micro 5.5)
• KubeVirtBMC version: v0.4.1

Additional context

Because we're going to work on #4, I'd expect this issue could be solved with that one.