[SCSI] fc-transport: Use packed modifier for fc_bsg_request structure.

The 32bit kernel does not add padding bytes in the fc_bsg_request structure
whereas the 64bit kernel adds padding bytes in the fc_bsg_request structure.
Due to this, structure elements gets mismatched with 32bit application and
64bit kernel.To resolve this, used packed modifier to avoid adding padding bytes.
Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>