Replicant

For many devices, we have code like that:

        rc = xmm626_kernel_smdk4412_power(client, modem_boot_fd, 1);
        rc |= xmm626_kernel_smdk4412_hci_power(client, 1);

        if (rc < 0) {
                ipc_client_log(client, "Turning the modem on failed");
                goto error;
        }

While it takes more time to write, it would be better to have two distinct
error messages:

        rc = xmm626_kernel_smdk4412_power(client, modem_boot_fd, 1);
        if (rc < 0) {
                ipc_client_log(client, "Turning the modem on failed");
                goto error;
        }

        rc = xmm626_kernel_smdk4412_hci_power(client, 1);

        if (rc < 0) {
                ipc_client_log(client, "Powering on the HCI bus failed");
                goto error;
        }