This patch combines my patch which statically initialises the crc32
tables so they can be used at any time (during initialisation) and
Joakim Tjernlund's patch to speed up the crc calculations by doing word
operations instead of exclusively byte.

The crc routines are used extensively in jffs2 where speed is very
important.

I need the crc32 routines to calculate a checksum on values read from an
eeprom which contain cpu speed and memory size information - so they are
needed very much earlier in the initialisation process than they are
currently available.