Merge branch 'stable/for-jens-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-linus

Pull a xen_blkfront fix from Konrad:

"It has one simple fix for the multi-queue support not showing up after
a block device was detached/re-attached."

* 'stable/for-jens-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen-blkfront: move negotiate_mq to cover all cases of new VBDs