Fix game not saving due to impossible check

[MtnDont]

• init_memcard_driver never returns 0 but does also return 1 as an OK
• Both emulators and PS2 hardware would stall at mcInit(MC_TYPE_MC), changing it to mcInit(MC_TYPE_XMC) allows saving

[fgsfdsfgs]

Upon checking ps2_drivers, it appears that the correct way to check for init_memcard_driver failure would be if (ret < 0), since both 0 and 1 are considered a success. For mcInit it would probably make sense to do something like this to catch both possible MC types:

    ret = mcInit(MC_TYPE_XMC);
    if (ret < 0) ret = mcInit(MC_TYPE_MC);
    if (ret < 0) {
        printf("ps2_memcard: mcInit failed: %d\n", ret);
        return false;
    }