[Darwin, PPC] Emit uppercase versions of ppc defines.

Emit __PPC__ (32b) and __PPC64__ (64bit) as per the other members
of the PowerPC port.

2019-06-23  Iain Sandoe  <iain@sandoe.co.uk>

	* config/rs6000/darwin.h: (__PPC__, __PPC64__): New.

From-SVN: r272602

gcc/ChangeLog

+2019-06-23  Iain Sandoe  <iain@sandoe.co.uk>
+
+	* config/rs6000/darwin.h: (__PPC__, __PPC64__): New.
+
 2019-06-22  Jeff Law  <law@redhat.com>
 
 	* config/avr/avr.c (TARGET_BUILTIN_SETJMP_FRAME_VALUE): Remove.

gcc/config/rs6000/darwin.h

@@ -54,7 +54,9 @@
   do							\
     {							\
       if (!TARGET_64BIT) builtin_define ("__ppc__");	\
+      if (!TARGET_64BIT) builtin_define ("__PPC__");	\
       if (TARGET_64BIT) builtin_define ("__ppc64__");	\
+      if (TARGET_64BIT) builtin_define ("__PPC64__");	\
       builtin_define ("__POWERPC__");			\
       builtin_define ("__NATURAL_ALIGNMENT__");		\
       darwin_cpp_builtins (pfile);			\