sound: fix oss/msnd_pinnacle module param type

Fix module parameter data type to eliminate build warning.

sound/oss/msnd_pinnacle.c:1727:1: warning: return from incompatible pointer type
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/oss/msnd_pinnacle.c

@@ -1631,7 +1631,7 @@ static int ide_irq __initdata = 0;
 static int joystick_io __initdata = 0;
 
 /* If we have the digital daugherboard... */
-static int digital __initdata = 0;
+static bool digital __initdata = false;
 #endif
 
 static int fifosize __initdata =	DEFFIFOSIZE;