GPU: Implement skip-drawing-to-active-field for interlaced mode

Currently only in the software renderer.

src/core/gpu_sw.cpp

@@ -574,6 +574,9 @@ void GPU_SW::ShadePixel(u32 x, u32 y, u8 color_r, u8 color_g, u8 color_b, u8 tex
   if ((bg_color.bits & mask_and) != 0)
     return;
 
+  if (m_GPUSTAT.SkipDrawingToActiveField() && BoolToUInt32(m_GPUSTAT.drawing_even_line) != (static_cast<u32>(y) & 1u))
+    return;
+
   SetPixel(static_cast<u32>(x), static_cast<u32>(y), color.bits | m_GPUSTAT.GetMaskOR());
 }