PM QoS: Correct pr_debug() misuse and improve parameter checks

Correct some pr_debug() misuse and add a stronger parameter check to
pm_qos_write() for the ASCII hex value case.  Thanks to Dan Carpenter
for pointing out the problem!
Signed-off-by: mark gross <markgross@thegnar.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

kernel/pm_qos_params.c

@@ -389,10 +389,12 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
 	} else if (count == 11) { /* len('0x12345678/0') */
 		if (copy_from_user(ascii_value, buf, 11))
 			return -EFAULT;
+		if (strlen(ascii_value) != 10)
+			return -EINVAL;
 		x = sscanf(ascii_value, "%x", &value);
 		if (x != 1)
 			return -EINVAL;
-		pr_debug(KERN_ERR "%s, %d, 0x%x\n", ascii_value, x, value);
+		pr_debug("%s, %d, 0x%x\n", ascii_value, x, value);
 	} else
 		return -EINVAL;