win32: clean up hidpi window scale behavior

Same as X11. An accurate dpi scale should always be reported and
UNFS_WINDOW_SIZE shouldn't take dpi scale as an additional multiplier.

video/out/w32_common.c

@@ -618,7 +618,7 @@ static void update_dpi(struct vo_w32_state *w32)
     }
 
     w32->dpi = dpi;
-    w32->dpi_scale = w32->opts->hidpi_window_scale ? w32->dpi / 96.0 : 1.0;
+    w32->dpi_scale = w32->dpi / 96.0;
     signal_events(w32, VO_EVENT_DPI);
 }
 
@@ -2092,8 +2092,8 @@ static int gui_thread_control(struct vo_w32_state *w32, int request, void *arg)
             return VO_FALSE;
 
         RECT *rc = w32->current_fs ? &w32->prev_windowrc : &w32->windowrc;
-        s[0] = rect_w(*rc) / w32->dpi_scale;
-        s[1] = rect_h(*rc) / w32->dpi_scale;
+        s[0] = rect_w(*rc);
+        s[1] = rect_h(*rc);
         return VO_TRUE;
     }
     case VOCTRL_SET_UNFS_WINDOW_SIZE: {
@@ -2102,9 +2102,6 @@ static int gui_thread_control(struct vo_w32_state *w32, int request, void *arg)
         if (!w32->window_bounds_initialized)
             return VO_FALSE;
 
-        s[0] *= w32->dpi_scale;
-        s[1] *= w32->dpi_scale;
-
         RECT *rc = w32->current_fs ? &w32->prev_windowrc : &w32->windowrc;
         resize_and_move_rect(w32, rc, s[0], s[1]);