RFR: JDK-8191324: SA cleanup -- part 2

[Jini George]

Hello,

Here's requesting reviews for some SA code cleanup.
ID: https://bugs.openjdk.java.net/browse/JDK-8191324
Webrev: http://cr.openjdk.java.net/~jgeorge/8191324/webrev.00/index.html

The changes here are primarily to:

1. Remove unused IA64 SA code.
2. Make changes to avoid error-prone redefinition of hotspot constants 
in SA Java code. Instead read it in through vmStructs and 
db.lookupIntConstant().
3. Make variable name changes in SA to align with the hotspot names.

The changes are straightforward.

Thanks much,
Jini.