[SCSI] libfc: fix statistics for FCP input/output megabytes

The statistics for InputMegabytes and OutputMegabytes are
misnamed.  They're accumulating bytes, not megabytes.

The statistic returned via /sys must be in megabytes, however,
which is what the HBA-API wants.  The FCP code needs to accumulate
it in bytes and then divide by 1,000,000 (not 2^20) before it
presented via sysfs.

This affects fcoe.ko only, not fnic.  The fnic driver
correctly by accumulating bytes and then converts to megabytes.

I checked that libhbalinux is using the /sys file directly without
conversion.

BTW, qla2xxx does divide by 2^20, which I'm not fixing here.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>