Eliminate warnings on Linux.
Eliminate warnings on Linux.

Interesting the warnings that came when POW2() was a macro.  Linux likes it
better as a function.

kingtaurus/vogl,ValveSoftware/vogl,bclemetsonblizzard/vogl,bclemetsonblizzard/vogl,bclemetsonblizzard/vogl,bclemetsonblizzard/vogl,ValveSoftware/vogl,kingtaurus/vogl,bclemetsonblizzard/vogl,kingtaurus/vogl,ValveSoftware/vogl,ValveSoftware/vogl,kingtaurus/vogl