Improve log message during live migration of UEFI-enabled VMs

[rosi-shapeblue]

problem

When performing live migration of a UEFI-enabled VM, the management server logs the following message even though migration completes successfully:

Live Migration of UEFI enabled VM : <vm-name> is not supported

This message can be confusing, as it appears even when the migration succeeds. It originates from the UEFI host filtering step, not from an actual failure.

versions

ACS 4.20.1

The steps to reproduce the bug

1. Deploy a VM with bootType=UEFI and bootMode=Secure (or Legacy).
2. Ensure destination hosts have host.uefi.enable=true.
3. Initiate live migration of the VM.
4. Observe that migration completes successfully, but the following appears in the management log:

2025-11-03 09:46:02,898 INFO [c.c.s.ManagementServerImpl] (qtp253011924-16:[ctx-fbedb526, ctx-e59ab56e]) (logid:06d7e6b7) Live Migration of UEFI enabled VM : i-2-15-VM is not supported

What to do about it?

The message should only be logged (as a warning or error) when migration truly cannot proceed - for example, when no UEFI-capable destination hosts are available.
Otherwise, a clearer debug/info message should indicate that UEFI host filtering is in progress.

[sureshanaparti]

@rosi-shapeblue log message is improved here - #11740, please check.