add HRFID to powerpc64

Reference: /n/sources/patch/applied/libmach-9c
Date: Wed Dec  5 19:49:03 CET 2007
Signed-off-by: forsyth@terzarima.net

--- /sys/src/libmach/9c/9.out.h	Wed Dec  5 19:48:36 2007
+++ /sys/src/libmach/9c/9.out.h	Wed Dec  5 19:48:33 2007
@@ -358,6 +358,9 @@
 	AREMDUV,
 	AREMDUVCC,
 
+	/* more 64-bit operations */
+	AHRFID,
+
 	ALAST
 };