e752x_edac: Simplify call to pci_get_device()

The last parameter, pvt->bridge_ck, is always NULL as far as I can
see, so just use that.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Aristeu Rozanski <aris@redhat.com>
Link: http://lkml.kernel.org/r/20140130091101.22f2b550@endymion.delvare
Cc: Mark Gross <mark.gross@intel.com>
Cc: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Borislav Petkov <bp@suse.de>