sound/oss/trident.c: fix incorrect test in trident_ac97_set()

If count reaches zero, the loop ends, but the postfix decrement still
subtracts: testing for 'count == 0' will not work.
Signed-off-by: NRoel Kluin <12o3l@tiscali.nl>
Reviewed-by: NRay Lee <ray-lk@madrabbit.org>
Acked-by: NMuli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

sound/oss/trident.c

@@ -2935,7 +2935,7 @@ trident_ac97_set(struct ac97_codec *codec, u8 reg, u16 val)
 	do {
 		if ((inw(TRID_REG(card, address)) & busy) == 0)
 			break;
-	} while (count--);
+	} while (--count);
 
 	data |= (mask | (reg & AC97_REG_ADDR));
 
@@ -2996,7 +2996,7 @@ trident_ac97_get(struct ac97_codec *codec, u8 reg)
 		data = inl(TRID_REG(card, address));
 		if ((data & busy) == 0)
 			break;
-	} while (count--);
+	} while (--count);
 	spin_unlock_irqrestore(&card->lock, flags);
 
 	if (count == 0) {