[media] enable COMPILE_TEST for ti-vbe

Allowing COMPILE_TEST here is trivial, but there's one missing
header to be added:

drivers/media/platform/ti-vpe/vpe.c: In function ‘vpe_probe’:
drivers/media/platform/ti-vpe/vpe.c:2266:56: error: ‘SZ_32K’ undeclared (first use in this function)
  dev->base = devm_ioremap(&pdev->dev, dev->res->start, SZ_32K);
                                                        ^

Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>