[7u] RFR 8035166: Remove dependency on EC classes from pkcs11 provider

[Alexey Bakhtin]

Hello Serge,

I see several issues with this patch:

sun/security/ec/ECPrivateKeyImpl.java
- ECUtil class is not referenced in the ECPrivateKeyImpl class. Import can be removed

org/jcp/xml/dsig/internal/dom/DOMKeyValue.java
- DomKeyValue class should be updated to instantiate ECParameters and NamedCurve classes in the correct namespace
This class is modified in the original JDK9 patch [1] but missed in the JDK11 and JDK8 because of different XML Dsig implementation.

[1] - http://hg.openjdk.java.net/jdk9/jdk9/jdk/rev/87fac66a55b4

Regards
Alexey