hwmon: (dell-smm) Fix warning on /proc/i8k creation error

The removal function is called regardless of whether
/proc/i8k was created successfully or not, the later
causing a WARN() on module removal.
Fix that by only registering the removal function
if /proc/i8k was created successfully.

Tested on a Inspiron 3505.

Fixes: 039ae58 ("hwmon: Allow to compile dell-smm-hwmon driver without /proc/i8k")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Acked-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20211112171440.59006-1-W_Armin@gmx.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/dell-smm-hwmon.c

@@ -627,10 +627,9 @@ static void __init i8k_init_procfs(struct device *dev)
 {
 	struct dell_smm_data *data = dev_get_drvdata(dev);
 
-	/* Register the proc entry */
-	proc_create_data("i8k", 0, NULL, &i8k_proc_ops, data);
-
-	devm_add_action_or_reset(dev, i8k_exit_procfs, NULL);
+	/* Only register exit function if creation was successful */
+	if (proc_create_data("i8k", 0, NULL, &i8k_proc_ops, data))
+		devm_add_action_or_reset(dev, i8k_exit_procfs, NULL);
 }
 
 #else