AFAICT, the fb_base of a drm_device's mode_config is never used.  It isn't
accessed by core drm, it isn't used by fbmem, and it isn't exposed to user
space.

Furthermore, it is probably supposed to be a physical address, not the
dma address mapped to the display controller, so this is just wrong.
Signed-off-by: NDaniel Kurtz <djkurtz@chromium.org>
Signed-off-by: NInki Dae <inki.dae@samsung.com>