[vector api] RFR: Fix byte vector test failures about bad ad file and unsupported vector size for AArch64

[Yang Zhang (Arm Technology China)]

Hi

On AArch64 platform, the following tests failed because of bad ad file and unsupported vector size.
jdk/incubator/vector/Byte128VectorTests.java
jdk/incubator/vector/Byte256VectorTests.java
jdk/incubator/vector/Byte512VectorTests.java
jdk/incubator/vector/ByteMaxVectorTests.java 

I have a patch which could fix these failures. Could you please help to review it?
http://cr.openjdk.java.net/~yzhang/vectorapi.vect4/webrev.00/

Regards,
Yang