svga: move index buffer bind flag assertion

The buffer bind flags can be promoted in svga_buffer_handle(), so
move the assertion after it. This has already been done for
vertex buffer in commit 6b4bf7e8be, but it misses the one for
index buffer.

Fixes assertion running WarThunder.

Reviewed-by: Neha Bhende <bhenden@vmware.com>
1 file changed