[PowerPC64] Fix FAIL: ExtraClassLoader execution - gij test

[Andrew Pinski]

> 
> Fixes two libjava testsuite failures on powerpc64-linux.  Bootstrapped
> and regression tested powerpc64-linux and powerpc-linux.  OK for 4.1 and
> 4.2?
> 
> 	* stacktrace.cc (UnwindTraceFn): For powerpc64, compare the function
> 	code entry not the function descriptor against _Unwind_GetRegionStart.

Isn't there a macro to do this?

As I would assume this is incorrect for IA64 and HPPA also.

-- Pinski