aarch64: Increase the number of feature words to 3

Now that most of the effort of updating the number of feature words is
handled by macros, add an additional one, taking the number of
supported features to 192.
diff --git a/include/opcode/aarch64.h b/include/opcode/aarch64.h
index c90a697..29dc094 100644
--- a/include/opcode/aarch64.h
+++ b/include/opcode/aarch64.h
@@ -295,7 +295,8 @@
 
 #define AA64_REPLICATE(SEP, BODY, ...)	\
   BODY (0, __VA_ARGS__) SEP		\
-  BODY (1, __VA_ARGS__)
+  BODY (1, __VA_ARGS__) SEP		\
+  BODY (2, __VA_ARGS__)
 
 /* Some useful SEP operators for use with replication.  */
 #define REP_COMMA ,