omap mmc: Remove broken MMC init code

Most of the omap1 MMC boards got broken by an earlier patch
138ab9f8. If you look closely,
the MMC init funtions are pretty much just stubs.

Remove broken init code to make room for cleaner MMC init code.

Cc: Pierre Ossman <drzeus-mmc@drzeus.cx>
Signed-off-by: Tony Lindgren <tony@atomide.com>