RFR: 8232602: ZGC: Make ZGranuleMap ZAddress agnostic

[Stefan Karlsson]

Hi all,

Please review this patch to make ZGranuleMap ZAddress agnostic.

https://cr.openjdk.java.net/~stefank/8232602/webrev.01/
https://bugs.openjdk.java.net/browse/JDK-8232602

Currently, the ZGranuleMap get and put functions take an address in the 
heap as a parameter. The address is then converted into an offset (into 
a heap view), before being scaled to a granule.

We want to be able to use the ZGranuleMap for physical memory offsets, 
and not only heap addresses. Therefore, I propose that we move the 
conversions from address to offset out from ZGranuleMap, and move it to 
the current users of ZGranuleMap.

This patch applies on-top of the patch for JDK-8232601.

Thanks,
StefanK