x86/platform/iosf_mbi: Convert PCIBIOS_* return codes to errnos

iosf_mbi_pci_{read,write}_mdr() use pci_{read,write}_config_dword()
that return PCIBIOS_* codes but functions also return -ENODEV which are
not compatible error codes. As neither of the functions are related to
PCI read/write functions, they should return normal errnos.

Convert PCIBIOS_* returns code using pcibios_err_to_errno() into normal
errno before returning it.

Fixes: 46184415 ("arch: x86: New MailBox support driver for Intel SOC's")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240527125538.13620-4-ilpo.jarvinen@linux.intel.com