scsi: qedi: tidy up a size calculation

The id_tbl->table pointer points to unsigned long so static checkers
complain that instead of 4 we should be allocating sizeof(long) bytes.

We're trying to allocate enough bits for the bitmap.  The size variable is
always 1024.  (1024 / 32 * 4) is the same as (1024 / 64 * 8) so this
doesn't change runtime, but this is the more idiomatic way to do it and
makes the static checker happy.

[mkp: typo]

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Manish Rangankar <Manish.Rangankar@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>