Bug 621043 - AIX: avmplus.h fails in xlC due to GCC-isms only on #ifdef __powerpc__. r=mrbkap.

--HG--
extra : convert_revision : ddf045b983f32d3f9a2cfc666ecbe825efe9b182

js/src/nanojit/avmplus.h

@@ -147,7 +147,7 @@ static inline unsigned __int64 rdtsc(void)
     return __rdtsc();
 }
 
-#elif defined(__powerpc__)
+#elif defined(__GNUC__) && defined(__powerpc__)
 
 # define AVMPLUS_HAS_RDTSC 1