The current trace prototypes and (matching) trace calls lead to
"unorthodox" PCI BDF notation in at least the stderr trace backend. For
example, the four BARs of a QXL video card at 00:01.0 (bus 0, slot 1,
function 0) are traced like this (PID and timestamps removed):

  pci_update_mappings_add d=0x7f14a73bf890 00:00.1 0,0x84000000+0x4000000
  pci_update_mappings_add d=0x7f14a73bf890 00:00.1 1,0x80000000+0x4000000
  pci_update_mappings_add d=0x7f14a73bf890 00:00.1 2,0x88200000+0x2000
  pci_update_mappings_add d=0x7f14a73bf890 00:00.1 3,0xd060+0x20

The slot and function values are in reverse order.

Stick with the conventional BDF notation.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Don Koch <dkoch@verizon.com>
Cc: qemu-trivial@nongnu.org
Fixes: 7828d750Signed-off-by: NLaszlo Ersek <lersek@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>