m53evk: Fix build failure due non-FSL kernel use with AMD GPU

The m53evk board uses the DENX kernel which is based in mainline and
does not has the need drivers for AMD GPU driver to build. This
patches makes it use the Framebuffer driver instead fixing a build
failure found in our autobuilder.

Change-Id: Iad1dfbb7f9ed342f374d9721228eff09e821377f
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Cc: Marek Vasut <marex@denx.de>