lynx-dev simple fix for 123- bug

[Laura Eaves]

Here is a simple change that fixes the 123- bug reported by purslow.
I tried it on several boundary conditions and it seems to work.
Hope you can put this in 2.8.2.  If the fix for some reason fails
on another test, the function containing the fix is only invoked
when processing the 123[g][+-] command.
So it shoulnd't affect anything else.
--le

--- old/GridText.c      Wed May 12 22:06:05 1999
+++ src/GridText.c      Mon May 17 17:16:28 1999
@@ -4077,7 +4077,7 @@
        int,    cur)
 {
     TextAnchor *a, *l = 0;
-    int scrtop = HText_getTopOfScreen()+1;
+    int scrtop = HText_getTopOfScreen(); /*XXX +1? */
     int curline = links[cur].anchor_line_num;
     int curpos = links[cur].lx;
     int on_screen = ( curline >= scrtop && curline < (scrtop + display_lines) 
);