jffs2_scan_eraseblock() - errors

[Curtis, Allen]

> >  INOCACHE_HASHSIZE was set to 1. Changed this to 128 and....
> > real	47.258s sys	47.25s
> 
> It's the first (and easy) part of the proof-of-concept which involves 
> moving said CRC32 check to later so the mount doesn't have to 
> wait for it.

With the CRC patch:
real	36.7s

PS: The version of scan.c we are using is 1.57. The patch note was for
1.51.2.3.