Enable unprefixed label setting via feature gate

Currently, unprefixed labels are not allowed, despite the existence of the
DisableAutoPrefix feature gate, which is intended for this purpose. This
change ensures that when DisableAutoPrefix is set to True, the namespace
addition is skipped, allowing unprefixed labels.

Signed-off-by: Feruzjon Muyassarov <[email protected]>

Author: fmuyassarov

docs/reference/feature-gates.md

@@ -55,8 +55,7 @@ to `false`, a NodeFeatureRule with
     foo: bar
 ```
 
-will turn into `feature.node.kubernetes.io/foo=bar` node label. With
-`DisableAutoPrefix` set to `true`, no prefix is added and the label will be
-filtered out.
-
-Note that taint keys are not affected by this feature gate.
+will be automatically prefixed, resulting in the node label
+`feature.node.kubernetes.io/foo=bar`. However, when `DisableAutoPrefix` is set
+to `true`, no prefix is added, and the label remains as `foo=bar`. Note that
+taint keys are not affected by this feature gate.

pkg/nfd-master/nfd-master.go

@@ -482,7 +482,6 @@ func (m *nfdMaster) filterFeatureLabels(labels Labels, features *nfdv1alpha1.Fea
 
 	return outLabels
 }
-
 func (m *nfdMaster) filterFeatureLabel(name, value string, features *nfdv1alpha1.Features) (string, error) {
 	// Check if Value is dynamic
 	var filteredValue string
@@ -504,7 +503,9 @@ func (m *nfdMaster) filterFeatureLabel(name, value string, features *nfdv1alpha1
 			return "", fmt.Errorf("namespace %q is not allowed", ns)
 		}
 	} else if err != nil {
-		return "", err
+		if !nfdfeatures.NFDFeatureGate.Enabled(nfdfeatures.DisableAutoPrefix) || err != validate.ErrUnprefixedKeysNotAllowed {
+			return "", err
+		}
 	}
 
 	// Skip if label doesn't match labelWhiteList