docs: virsh: Document the IO mode 'io_uring'
docs: virsh: Document the IO mode 'io_uring'

Signed-off-by: Lin Ma <b672e1c95326414c5ec2f68d68657d26580eb0bc@suse.de>
Reviewed-by: Michal Privoznik <83d82aaba2eed257f4814b0c239c260c4caaadf0@redhat.com>

nertpinx/libvirt,zippy2/libvirt,jfehlig/libvirt,nertpinx/libvirt,jardasgit/libvirt,crobinso/libvirt,olafhering/libvirt,libvirt/libvirt,crobinso/libvirt,jfehlig/libvirt,libvirt/libvirt,zippy2/libvirt,libvirt/libvirt,jardasgit/libvirt,jfehlig/libvirt,jardasgit/libvirt,olafhering/libvirt,crobinso/libvirt,olafhering/libvirt,jardasgit/libvirt,zippy2/libvirt,zippy2/libvirt,jardasgit/libvirt,nertpinx/libvirt,libvirt/libvirt,nertpinx/libvirt,olafhering/libvirt,jfehlig/libvirt,nertpinx/libvirt,crobinso/libvirt