RFR 8179903: Clean up SPARC 32-bit support

[George Triantafillou]

Please review this fix to clean up SPARC 32-bit support.

JBS: https://bugs.openjdk.java.net/browse/JDK-8179903
webrev: 
http://cr.openjdk.java.net/~gtriantafill/8179903-webrev/webrev/index.html 
<http://cr.openjdk.java.net/%7Egtriantafill/8179903-webrev/webrev/index.html>

This is a followup RFE to "JDK-8150388 Remove SPARC 32-bit support". The 
work includes addressing formatting, 32-bit comments, and other issues 
that Kim raised after JDK-8150388 was reviewed and checked in.

Built and tested on solaris-sparcv9-debug, solaris-x64-debug with the 
nsk.jvmti, nsk.jdwp, and nsk.jdi testlists.

Thanks.

-George