can: peak/pci: fix potential bug when probe() fails

can: peak/pci: fix potential bug when probe() fails

commit 5c2cb02edf79ad79d9b8d07c6d52243a948c4c9f upstream.

PCI/PCIe drivers for PEAK-System CAN/CAN-FD interfaces do some access to the
PCI config during probing. In case one of these accesses fails, a POSITIVE
PCIBIOS_xxx error code is returned back. This POSITIVE error code MUST be
converted into a NEGATIVE errno for the probe() function to indicate it
failed. Using the pcibios_err_to_errno() function, we make sure that the
return code will always be negative.

Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>