rs6000: Testcase 20050830-1.c no longer fails (PR66612)

Bin's commit r246810, for PR80153, fixes 20050830-1.c for -m64 (it
already passed for -m32).  So, this patch removes the remaining xfail.


gcc/testsuite/
	PR tree-optimization/66612
	* gcc.target/powerpc/20050830-1.c: Remove xfail.

From-SVN: r246939