mx23_olinuxino: convert MMC to driver model

Convert the Olimex Olinuxino board's support for MMC to driver model following
Fabio Estevam's excellent example from:

	commit: 23013aa9619881290dbeb6217f1fab863869050e:
	mx23evk: Convert to driver model

Signed-off-by: Trevor Woerner <twoerner@gmail.com>
3 files changed