re PR target/51274 (Starting with GCC 4.5, powerpc generated different code for x != 0.)

gcc/
	PR target/51274
	PR target/53087
	* config/rs6000/rs6000.md (ne0si): Remove unnecessary
	earlyclobber.  Merge with...
	(ne0di): ... to...
	(ne0_<mode>): New.
	(plus_ne0si): Merge with...
	(plus_ne0di): ... to...
	(plus_ne0_<mode>): New.
	(compare_plus_ne0si): Merge with...
	(compare_plus_ne0di)... to...
	(compare_plus_ne0_<mode>): New.
	(compare_plus_ne0_<mode>_1): New.
	(plus_ne0si_compare): Merge with...
	(plus_ne0di_compare)... to...
	(plus_ne0_<mode>_compare): New.

gcc/testsuite/
	PR target/51274
	PR target/53087
	* gcc.target/powerpc/ppc-ne0-1.c: New.

From-SVN: r191752