video: adf: fbdev: add stubs for kernels without ADF_FBDEV

Change-Id: I42e087cddc29f6b93749791606e80dbd3e6f59ce
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Git-commit: 10689a3985d3a1689bd4f36f0d5327b7d655d1bb
Git-repo: https://android.googlesource.com/kernel/common.git


Signed-off-by: Ian Maund <imaund@codeaurora.org>