Import required enum and remove unused variables

Import PKCS11Exception return values enum, to adapt code for the local backport of openjdk/jdk@7ab6dc8

Remove unused variables forgotten in rh-openjdk/jdk#14 (see rh-openjdk/jdk#21)

Author: franferrax

src/jdk.crypto.cryptoki/share/classes/sun/security/pkcs11/FIPSKeyImporter.java

@@ -45,6 +45,7 @@
 import sun.security.pkcs11.wrapper.CK_ATTRIBUTE;
 import sun.security.pkcs11.wrapper.CK_MECHANISM;
 import static sun.security.pkcs11.wrapper.PKCS11Constants.*;
+import static sun.security.pkcs11.wrapper.PKCS11Exception.*;
 import sun.security.pkcs11.wrapper.PKCS11Exception;
 import sun.security.rsa.RSAPrivateCrtKeyImpl;
 import sun.security.rsa.RSAUtil;
@@ -71,9 +72,6 @@ final class FIPSKeyImporter {
     private static volatile Provider sunECProvider = null;
     private static final ReentrantLock sunECProviderLock = new ReentrantLock();
 
-    private static volatile KeyFactory DHKF = null;
-    private static final ReentrantLock DHKFLock = new ReentrantLock();
-
     static Long importKey(SunPKCS11 sunPKCS11, long hSession, CK_ATTRIBUTE[] attributes)
             throws PKCS11Exception {
         long keyID = -1;