RFR: JDK-8062045: Update svc regression tests to extend the default security policy instead of override

[Alexander Kulyakhtin]

Hi,

Could you, please, review the small test-only changes below:

CR: https://bugs.openjdk.java.net/browse/JDK-8062045 "Update svc regression tests to extend the default security policy instead of override"
Webrev: http://cr.openjdk.java.net/~akulyakh/8062045/webrev/

This changes main/othervm/policy to main/othervm/java.security.policy in the tests from the jdk_svc tests group.
These tests need to extend the default system policy, not to override it. Therefore they should use 'java.security.policy'.

The changes are similar to what has been previously done in JDK-8043277 and JDK-8062047

Best regards,
Alexander