err remains uninitialized of pci_request_regions fails.

Found by Thorsten Kukuk, I added a few more checks.
Signed-off-by: NOlaf Hering <olh@suse.de>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>