Clean up MMC/SD fault handling for transfers with data stages:

 - After DMA errors, always issue any STOP needed; aborting DMA
   on the host is not sufficient to reset the card's state.

 - It does that already after data or command errors; but also:
     * Always reset the data and command state machines, instead
       of just the command machine (and just for data "CRC" errors)
     * Report how many blocks were transferred (resolving FIXMEs)

There are probably still a few holes in fault handling, but these
updates resolved some problems I was (briefly) able to reproduce
by running a DM6446 quite a bit faster than it's supposed to be
able to handle.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>