[PATCH] Fix warnings from icc

icc spewed a bunch of warnings on building fio, but it did actually build
and work. Some of them are real bugs, most are just "helpful" warnings.

icc doesn't like pointer arithmetic, however these are not fixed up. It
works as-is, just ignore those class of warnings.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>