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

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

Signed-off-by: Colin Ian King <[e-mail]>
Reviewed-by: Shuah Khan <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Takashi Iwai <[e-mail]>

tools/testing/selftests/alsa/mixer-test.c

···
 
 		err = snd_ctl_poll_descriptors_count(card_data->handle);
 		if (err != 1) {
-			ksft_exit_fail_msg("Unexpected desciptor count %d for card %d\n",
+			ksft_exit_fail_msg("Unexpected descriptor count %d for card %d\n",
 					   err, card);
 		}
 
···
 						       &(ctl->card->pollfd),
 						       1, &revents);
 		if (err < 0) {
-			ksft_print_msg("snd_ctl_poll_desciptors_revents() failed for %s: %d\n",
+			ksft_print_msg("snd_ctl_poll_descriptors_revents() failed for %s: %d\n",
 				       ctl->name, err);
 			return err;
 		}
 		if (revents & POLLERR) {
-			ksft_print_msg("snd_ctl_poll_desciptors_revents() reported POLLERR for %s\n",
+			ksft_print_msg("snd_ctl_poll_descriptors_revents() reported POLLERR for %s\n",
 				       ctl->name);
 			return -1;
 		}