The test case drivers/dma-buf/udmabuf need this kernel config enabled

CONFIG_UDMABUF=y
Signed-off-by: NNaresh Kamboju <naresh.kamboju@linaro.org>
Reviewed-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NShuah Khan <skhan@linuxfoundation.org>