intel-spi: Fix compile error when errno is not available
intel-spi: Fix compile error when errno is not available

fwupd/fwupd,fwupd/fwupd,hughsie/fwupd,fwupd/fwupd,fwupd/fwupd,hughsie/fwupd,hughsie/fwupd,hughsie/fwupd