fix: ignore BMC info if username or password are not set

This happens during initial discovery of the server, when first BMC IP
is set, but username and password are not set.

Signed-off-by: Andrey Smirnov <andrey.smirnov@talos-systems.com>
(cherry picked from commit 229dae1)

app/sidero-controller-manager/internal/power/factory.go

@@ -39,6 +39,11 @@ func NewManagementClient(ctx context.Context, client client.Client, spec *v1alph
 			}
 		}
 
+		if bmcSpec.User == "" || bmcSpec.Pass == "" {
+			// no username and password, BMC information is not fully populated yet
+			return fakeClient{}, nil
+		}
+
 		if bmcSpec.Interface == "" {
 			bmcSpec.Interface = "lanplus"
 		}