vga: Simplify vga_draw_blank() a bit

The test for surface_bits_per_pixel() isn't necessary anymore,
the 8bpp case never happens.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>

hw/display/vga.c

@@ -1682,7 +1682,7 @@ static void vga_draw_graphic(VGACommonState *s, int full_update)
 static void vga_draw_blank(VGACommonState *s, int full_update)
 {
     DisplaySurface *surface = qemu_console_surface(s->con);
-    int i, w, val;
+    int i, w;
     uint8_t *d;
 
     if (!full_update)
@@ -1690,15 +1690,10 @@ static void vga_draw_blank(VGACommonState *s, int full_update)
     if (s->last_scr_width <= 0 || s->last_scr_height <= 0)
         return;
 
-    if (surface_bits_per_pixel(surface) == 8) {
-        val = rgb_to_pixel32(0, 0, 0);
-    } else {
-        val = 0;
-    }
     w = s->last_scr_width * surface_bytes_per_pixel(surface);
     d = surface_data(surface);
     for(i = 0; i < s->last_scr_height; i++) {
-        memset(d, val, w);
+        memset(d, 0, w);
         d += surface_stride(surface);
     }
     dpy_gfx_update(s->con, 0, 0,