RFR(xs): 8187228: [aix] make data segment page size 64K by default

[Thomas Stüfe]

Hi all,

may I please have a review for the following AIX-only patch.

Issue:
https://bugs.openjdk.java.net/browse/JDK-8187228

webrev:
http://cr.openjdk.java.net/~stuefe/webrevs/8187228-make-data
-segment-page-size-64K-by-default/webrev.00/webrev/

It changes the default page size for the data segment (C-heap and Posix
Thread Stacks) to 64K.

For completeness and simplicity sake, it also changes default page size for
text segment and primordial thread stacl to 64K, but that does not matter
much.

For more details, please see the issue description.

Thank you, Thomas