The write parameter in mmc_set_data_timeout() is redundant as the
data structure contains information about the direction of the
transfer.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Convert the MMC layer to use standard error codes and not its own,
incompatible values.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Make sure all headers in the files reflect their true position
in the tree.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Move protocol operations and definitions into their own files
in an effort to separate protocol handling and bus
arbitration more clearly.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>