Revert "MAINTAINERS: add entry for exynos mipi display drivers"

This reverts commit 5eb1eb4e.

The commit above breaks alphabetical ordering and I have the same
entry at the correct position in my tree. Not reverting this one
would result in duplicated maintainer entries.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>