rg_display: fixed rg_display_clear_rect being obviously wrong

Author: ducalex

components/retro-go/rg_display.c

@@ -606,9 +606,12 @@ void rg_display_clear_rect(int left, int top, int width, int height, uint16_t co
     if (width < 0 || height < 0)
         return;
 #if USE_SCREEN_BUFFER
-    uint16_t *buffer = lcd_get_fb_ptr(left, top);
-    for (int i = 0; i < pixels_remaining; ++i)
-        buffer[i] = color_le;
+    for (int y = 0; y < height; ++y)
+    {
+        uint16_t *buffer = lcd_get_fb_ptr(left, top + y);
+        for (int x = 0; x < width; ++x)
+            buffer[i] = color_le;
+    }
 #else
     const uint16_t color_be = (color_le << 8) | (color_le >> 8);
     lcd_set_window(screen_left, screen_top, width, height);