Fixed crash - need to save and restore rbx around cpuid, since the compiler may be assuming the stack pointer isn't being modified when filling in %0. I did it around each call to cpuid which isn't strictly necessary, but is definitely future proof. :)

The test programs in this directory tree are for demonstrating and
testing the functionality of the SDL library, and are placed in the
public domain.

October 28, 1997
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	Sam Lantinga				(slouken@libsdl.org)