This patch adds support for virtual IOMMU to the vmxnet3 module.  We
switch to DMA consistent mappings for anything we pass to the device.
There were a few places where we already did this, but using pci_blah();
these have been fixed to use dma_blah(), along with all new occurrences
where we've replaced kmalloc() and friends.

Also fix two small bugs:
1) use after free of rq->buf_info in vmxnet3_rq_destroy()
2) a cpu_to_le32() that should have been a cpu_to_le64()
Acked-by: George Zhang <georgezhang@vmware.com>
Acked-by: Aditya Sarwade <asarwade@vmware.com>
Signed-off-by: Andy King <acking@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>