[AD] [patch] merge_fonts() doc

[Daniel Schlyder <daniel@xxxxxxxxxx>]

There is an error in merge_fonts()'s example code. The final line should be

destroy_font(tempfont);

not

destroy_font(combined_font);

Patch attached. (Maybe too tiny a thing to submit a patch for, I dunno :))

Index: docs/src/allegro._tx
===================================================================
--- docs/src/allegro._tx	(revision 7542)
+++ docs/src/allegro._tx	(working copy)
@@ -7159,7 +7159,7 @@
       destroy_font(lower_range);
       destroy_font(upper_range);
       destroy_font(capitals);
-      destroy_font(combined_font);<endblock>
+      destroy_font(tempfont);<endblock>
 @retval
    Returns a pointer to the new font or NULL on error. Remember that you are
    responsible for destroying the font when you are finished with it to