Several fixes for mmc_delay():
* Repair if-clause that was supposed to detect sub-hz delays.
* Change yield() to cond_resched() as yield() no longer has the
semantics we desire.
* mmc_delay() is used to guarantee protocol delays, so we cannot
return early (i.e. use _interruptable).
Based on patch by Amol Lad.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
73778120c4