make -vvv display the parse tree in checkwps. Fix a potential bug in the parser where recursive tags (the playlist viewier) would share params with its parant which meant bad things

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@27677 a1c6a512-1295-4272-9138-f99709370657

tools/checkwps/checkwps.c

@@ -300,6 +300,8 @@ int main(int argc, char **argv)
         }
 
         printf("WPS parsed OK\n\n");
+        if (wps_verbose_level>2)
+            skin_debug_tree(wps.tree);
         filearg++;
     }
     return 0;