mei: convert PCI error to common errno

mei: convert PCI error to common errno

Ensure that callers receive only < 0 return value on error.
Convert PCI error returned by pci_read_config_dword()
to common errno before returning from function.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Link: https://patch.msgid.link/20260201094358.1440593-6-alexander.usyskin@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>