Merge pull request #38261 from tanshanshan/more-readable

Automatic merge from submit-queue (batch tested with PRs 37701, 36702, 37145, 37424, 38261)

replace err with nil when err is nil

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**What this PR does / why we need it**:

When err is nil ,replace err with nil, that can make code more readable

Thanks.
**Special notes for your reviewer**:

**Release note**:
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pkg/cloudprovider/plugins.go

@@ -71,7 +71,7 @@ func CloudProviders() []string {
 }
 
 // GetCloudProvider creates an instance of the named cloud provider, or nil if
-// the name is not known.  The error return is only used if the named provider
+// the name is unknown.  The error return is only used if the named provider
 // was known but failed to initialize. The config parameter specifies the
 // io.Reader handler of the configuration file for the cloud provider, or nil
 // for no configuation.

plugin/pkg/admission/persistentvolume/label/admission.go

@@ -124,7 +124,7 @@ func (l *persistentVolumeLabel) findAWSEBSLabels(volume *api.PersistentVolume) (
 		return nil, err
 	}
 
-	return labels, err
+	return labels, nil
 }
 
 // getEBSVolumes returns the AWS Volumes interface for ebs
@@ -169,7 +169,7 @@ func (l *persistentVolumeLabel) findGCEPDLabels(volume *api.PersistentVolume) (m
 		return nil, err
 	}
 
-	return labels, err
+	return labels, nil
 }
 
 // getGCECloudProvider returns the GCE cloud provider, for use for querying volume labels