Gas Doc: Update example of how .altmacro affects the interpretation of macro arguments.

  PR 31255
diff --git a/gas/doc/as.texi b/gas/doc/as.texi
index 56b5b75..42db11e 100644
--- a/gas/doc/as.texi
+++ b/gas/doc/as.texi
@@ -6231,27 +6231,22 @@
 Thus for example:
 
 @example
-.altmacro
 .macro foo bar=1, baz=2
 .print "\bar \baz"
 .endm
 
 foo baz=3
+.altmacro
+foo baz=3
 @end example
 
 Will print:
 
 @smallexample
+1 3
 baz=3 2
 @end smallexample
 
-Rather than the expected:
-
-@smallexample
-1 3
-@end smallexample
-
-
 @end table
 
 Note that since each of the @var{macargs} can be an identifier exactly