Pull the error code <-> error string mapping tables out of the function
so the code becomes readable. This lets me see the real flesh of the
functions, without all that flab clouding the view.

Note: There is a checkpatch issue with quoted strings across multiple
      lines. I will fix that in a subsequent patch to keep the changes
      small and separate.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>