RFR: 8301095: [s390x] TestDwarf.java fails

[Amit Kumar]

TestDwarf.java fails on s390 due to incorrect returned frame. for dereference_null crash, the (return) pc was selected from gpr14 (in accordance with z-ABI) but correct (return) pc was present at "return_pc" offset. This PR introduces an additional check for the frame type detection. 
Special Thanks to @RealLucy

-------------

Commit messages:
 - updates header year
 - adds additional check for frame detection

Changes: https://git.openjdk.org/jdk/pull/12306/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12306&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8301095
  Stats: 10 lines in 1 file changed: 7 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/12306.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12306/head:pull/12306

PR: https://git.openjdk.org/jdk/pull/12306