staging: most: remove unnecessary field initialization

Since conf->extra_len has already been reset in most_start_channel() when
function hdm_configure_channel() gets called, it can safely be removed
here.
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/most/hdm-usb/hdm_usb.c

@@ -771,7 +771,6 @@ static int hdm_configure_channel(struct most_interface *iface, int channel,
 	    !((conf->data_type == MOST_CH_ISOC_AVP) &&
 	      (conf->packets_per_xact != 0xFF))) {
 		mdev->padding_active[channel] = false;
-		conf->extra_len = 0;
 		goto exit;
 	}