svga: src surface for IntraSurfaceCopy cannot be multisample

Fixes SVGA Driver Errors with piglit test arb_copy_image-targets

Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Neha Bhende <bhenden@vmware.com>

src/gallium/drivers/svga/svga_pipe_blit.c

@@ -350,6 +350,10 @@ can_blit_via_intra_surface_copy(struct svga_context *svga,
    if (!svga_have_vgpu10(svga))
       return false;
 
+   /* src surface cannot be multisample */
+   if (blit_info->src.resource->nr_samples > 1)
+      return false;
+
    if (!sws->have_intra_surface_copy)
       return false;