ioport: remove LITTLE_ENDIAN mark for portio

ioport: remove LITTLE_ENDIAN mark for portio

Setting it to LE forces a byte swap when host != guest endian but
this makes no sense at all.

Herve made the suggestion upon observing that word writes/reads
were broken into byte writes/reads in such a way as to assume
devices are interpret registers as LE.

However, even if this were a problem, marking the region as LE is
not useful because what's essentially happening here is that LE is
open coded.  So by marking it LE in MemoryRegionOps, we're doing a
superflous swap.

Now, the portio code is suspicious to begin with.  The dispatch
layer really has no purpose in splitting I/O requests in the first
place...

Cc: Hervé Poussineau <[email protected]>
Cc: Alex Graf <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Signed-off-by: Anthony Liguori <[email protected]>