[SCSI] be2iscsi: Check ASYNC PDU Handle corresponds to HDR/DATA Handle

For each ASYNC PDU received there is an HDR and DATA handle for it.
There will be only 1 HDR ASYNC Handle, but DATA Handle can be more
than 1 for each ASYNC PDU received. Checking if the ASYNC Handle
correspongs to HDR or DATA while returning the Handle to the free list.
hwi_free_async_msg just return the handles to the free list. No return
values are needed so changing the return type to void.

Signed-off-by: John Soni Jose <sony.john-n@emulex.com>
Signed-off-by: Jayamohan Kallickal <jayamohan.kallickal@emulex.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>