B08021 scroll_amount wincap option

> - I'd like to see another option added: scroll_amount. In
>   combination with scroll_margin, this would control the amount
>   of squares the screen is scrolled when the scroll_margin is
>   reached (currently, this amount is 1, but if I recall
>   correctly, it used to be more). For example, if both were 5,
>   when you came within 5 spaces of the left screen border, the
>   screen would shift 5 spaces to the right).

win/win32/mhmap.h

@@ -16,5 +16,6 @@ int mswin_map_mode(HWND hWnd, int mode);
 #define ROGUE_LEVEL_MAP_MODE		MAP_MODE_ASCII12x16	
 
 #define DEF_CLIPAROUND_MARGIN  5
+#define DEF_CLIPAROUND_AMOUNT  1
 
 #endif /* MSWINMapWindow_h */