Need to check whether the variable is nil

[QiAnXinCodeSafe]

According to line 89, resq may be nil, and resp.Body in line 96 will cause a crash. By reading the previous code, resq cannot be nil, so we can remove the comparison in line 89. https://github.com/oracle/oci-cloud-controller-manager/blob/220ab897fd3e8b1bd4b6b6d13a072f477453c073/pkg/oci/instance/metadata/instance_metadata.go#L89-L96