Add kmsan for virtqueue_dma_map_single_attrs to fix:

BUG: KMSAN: uninit-value in receive_buf+0x45ca/0x6990
 receive_buf+0x45ca/0x6990
 virtnet_poll+0x17e0/0x3130
 net_rx_action+0x832/0x26e0
 handle_softirqs+0x330/0x10f0
 [...]

Uninit was created at:
 __alloc_pages_noprof+0x62a/0xe60
 alloc_pages_noprof+0x392/0x830
 skb_page_frag_refill+0x21a/0x5c0
 virtnet_rq_alloc+0x50/0x1500
 try_fill_recv+0x372/0x54c0
 virtnet_open+0x210/0xbe0
 __dev_open+0x56e/0x920
 __dev_change_flags+0x39c/0x2000
 dev_change_flags+0xaa/0x200
 do_setlink+0x197a/0x7420
 rtnl_setlink+0x77c/0x860
 [...]
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Tested-by: Alexander Potapenko <glider@google.com>
Message-Id: <20240606111345.93600-1-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>  # s390x
Acked-by: Jason Wang <jasowang@redhat.com>