mtd/r852: Fixes in case of DMA timeout

* Don't call complete on dma completion
* do a INIT_COMPLETE before using it each time
* Report DMA read error via ecc 'correct'

I finally managed to make my system do suspend to ram propertly, and I see that
if card was inserted during suspend (while system was off), I get dma timeouts
on resume. Simple card reinsert solves the issue.
This patch solves a crash that would happen otherwise

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>