[OpenJDK 2D-Dev] RFR: 8220528: [AIX] Fix basic Xinerama and Xrender functionality

[Volker Simonis]

Hi,

can I please have a review for the following change which fixes
Xinerama and Xrender support on AIX:

http://cr.openjdk.java.net/~simonis/webrevs/2019/8220528/
https://bugs.openjdk.java.net/browse/JDK-8220528

The change basically fixes the way how the corresponding libraries
(libXext and libXrender) get loaded on AIX and does some cleanups with
regards to the various platform macros. I've also added some debug
tracing to the Xrender initialization code similar to the Xinerama
initialization.

Thank you and best regards,
Volker