Build on master fails

Hello!

I'm trying to compile sndio source.

I get these errors:
```
./configure --enable-alsa --enable-rmidi --enable-umidi --with-libbsd
--enable-oss
$ make -j4
...
sio_oss.c:69:4: error: use of undeclared identifier 'AFMT_U24_BE'
        { AFMT_U24_BE, 24, 3, 0, 0, 0 },
          ^
sio_oss.c:71:4: error: use of undeclared identifier 'AFMT_U24_LE'
        { AFMT_U24_LE, 24, 3, 0, 1, 0 },
          ^
sio_oss.c:76:4: error: use of undeclared identifier 'AFMT_U32_BE'
        { AFMT_U32_BE, 32, 4, 0, 0, 1 },
          ^
sio_oss.c:77:4: error: use of undeclared identifier 'AFMT_U32_LE'
        { AFMT_U32_LE, 32, 4, 0, 1, 1 },
          ^
...
```

Looking at the OSS source it seems there are no formats named
AFMT_U24_BE, AFMT_U24_LE, AFMT_U32_BE and AFMT_U32_LE.

I simply removed those and the build completed successfully.

I've attached the patch. Though I'm sot sure if this is the correct
way...

Thanks!

Regards,
Avinash Sonawane (rootKea)
https://www.rootkea.me