Pull swiotlb fix from Konrad Rzeszutek Wilk:
 "One tiny fix for ARM64 where we could allocate the SWIOTLB twice"

* 'stable/for-linus-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  xen/swiotlb: don't initialize swiotlb twice on arm64