staging: most: sound: remove overcautious argument checking

The interface pointer passed to a component API function cannot be NULL.
This patch removes the unnecessary sanity check of this argument.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Link: https://lore.kernel.org/r/1592924855-25569-6-git-send-email-christian.gromm@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/most/sound/sound.c

@@ -531,9 +531,6 @@ static int audio_probe_channel(struct most_interface *iface, int channel_id,
 	char *sample_res;
 	char arg_list_cpy[STRING_SIZE];
 
-	if (!iface)
-		return -EINVAL;
-
 	if (cfg->data_type != MOST_CH_SYNC) {
 		pr_err("Incompatible channel type\n");
 		return -EINVAL;