RFR (S) 8074817: Resolve disabled warnings for libverify

[Aleksey Shipilev]

Bug:
  https://bugs.openjdk.java.net/browse/JDK-8074817

Fix:
  http://cr.openjdk.java.net/~shade/8074817/webrev.03/

This hopefully resolves warnings in libverify. See bug report for warnings list.

Testing: jdk-submit, local {Linux, Windows} x86_64 builds

Thanks,
-Aleksey