Audio: fix recorder_wav.ino typo

[ous50]

replace the recoding_cannel_number -> recoding_channel_number to avoid confusion

[SPRESENSE]

@ous50
Thank you for your contribution!

Please change the target branch from master to develop.
(See https://github.com/sonydevworld/spresense-arduino-compatible/blob/master/CONTRIBUTING.md)

[SPRESENSE]

Hi @ous50 san

I found the same typo in another files
If you could fix them all, I would greatly appreciate it.

./recorder_objif/recorder_objif.ino
./recorder_wav_objif/recorder_wav_objif.ino
./recorder_wav_split/recorder_wav_split.ino

Thanks.