[media] Correct and add some parameter descriptions

>From 70d02ce19f64fae4ceee563501e8462a76e17b91 Mon Sep 17 00:00:00 2001
Signed-off-by: Hans Petter Selasky <hselasky@c2i.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/tda7432.c

@@ -49,10 +49,11 @@ static int maxvol;
 static int loudness; /* disable loudness by default */
 static int debug;	 /* insmod parameter */
 module_param(debug, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Set debugging level from 0 to 3. Default is off(0).");
 module_param(loudness, int, S_IRUGO);
-MODULE_PARM_DESC(maxvol,"Set maximium volume to +20db (0), default is 0db(1)");
+MODULE_PARM_DESC(loudness, "Turn loudness on(1) else off(0). Default is off(0).");
 module_param(maxvol, int, S_IRUGO | S_IWUSR);
-
+MODULE_PARM_DESC(maxvol, "Set maximium volume to +20dB(0) else +0dB(1). Default is +20dB(0).");
 
 
 /* Structure of address and subaddresses for the tda7432 */