Merge remote-tracking branch 'remotes/bonzini/scsi-next' into staging

* remotes/bonzini/scsi-next:
  virtio-scsi: define dummy handle_output for vhost-scsi vqs
  block/iscsi: drop obsolete pointers from iscsi_co_writev
  block/iscsi: fix init value for iTask->retries
  block/iscsi: bump libiscsi requirement to 1.9.0
  virtio-scsi: add support for the any_layout feature
  virtio-scsi: introduce virtio_scsi_complete_cmd_req
  virtio-scsi: prepare sense data handling for any_layout
  virtio-scsi: add extra argument and return type to qemu_sgl_concat
  virtio-scsi: add target swap for VirtIOSCSICtrlTMFReq fields
  virtio-scsi: start preparing for any_layout
  util: add return value to qemu_iovec_concat_iov
  megasas: use PCI DMA API
  scsi: Print command name in debug
  scsi-disk: fix bug in scsi_block_new_request() introduced by commit 137745c
  scsi-disk.c: Fix compilation with -DDEBUG_SCSI
  block/iscsi: use 16 byte CDBs only when necessary
  block/iscsi: fix potential segfault on early callback
  block/iscsi: handle BUSY condition

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>