Fix "libedit" to use the proper symbols when checking

for Sun or HP (no <sys/ttydefaults.h> there),
and include AIX in that exception list.

Originally done by Kent Boortz for 5.1.32 on 2009-02-11 + 12
and now backported into 5.1.31sp1

cmd-line-utils/libedit/readline/readline.h

@@ -66,7 +66,7 @@ typedef KEYMAP_ENTRY *Keymap;
 
 #ifndef CTRL
 #include <sys/ioctl.h>
-#if !defined(__sun__) && !defined(__hpux__)
+#if !defined(__sun) && !defined(__hpux) && !defined(_AIX)
 #include <sys/ttydefaults.h>
 #endif
 #ifndef CTRL