kselftest: alsa: fix spelling mistake "desciptor" -> "descriptor"

There are some spelling mistakes in some ksft messages. Fix them.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20220207092235.240284-1-colin.i.king@gmail.com


Signed-off-by: Takashi Iwai <tiwai@suse.de>