drm/vmwgfx: Enable SVGA_3D_CMD_DX_SET_PREDICATION

commit 1883598d upstream.

Fixes piglit tests nv_conditional_render-* crashes.

Signed-off-by: Charmaine Lee <charmainel@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>