pci_get_device does a pci_dev_get, so pci_dev_put needs to be called in an
error case

The problem was fixed using the following semantic patch.
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@exists@
type T1,T2;
identifier E;
statement S,S1;
expression x1,x2,x3;
expression test;
int ret != 0;
@@

  struct pci_dev *E;
  ...
(
  E = \(pci_get_slot\|pci_get_device\|pci_get_bus_and_slot\)(...);
  if (E == NULL) S
|
  if ((E = \(pci_get_slot\|pci_get_device\|pci_get_bus_and_slot\)(...)) == NULL) S
)
  ... when != pci_dev_put(...,(T1)E,...)
      when != if (E != NULL) { ... pci_dev_put(...,(T1)E,...); ...}
      when != x1 = (T1)E
      when != E = x3;
      when any
(
  if (E == NULL) S1
|
  if (test)
+   {
(
+   pci_dev_put(E);
    return;
|
+   pci_dev_put(E);
    return ret;
)
+   }
|
  if (test) {
    ... when != pci_dev_put(...,(T2)E,...)
        when != if (E != NULL) { ... pci_dev_put(...,(T2)E,...); ...}
        when != x2 = (T2)E
(
+   pci_dev_put(E);
    return;
|
+   pci_dev_put(E);
    return ret;
)
  }
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>