ipmi:ssif: NULL thread on error

commit a8aebe93a4938c0ca1941eeaae821738f869be3d upstream.

Cleanup code was checking the thread for NULL, but it was possibly
a PTR_ERR() in one spot.

Spotted with static analysis.

Link: https://sourceforge.net/p/openipmi/mailman/message/59324676/
Fixes: 75c486cb1bca ("ipmi:ssif: Clean up kthread on errors")
Cc: <stable@vger.kernel.org> # 91eb7ec72612: ipmi:ssif: Remove unnecessary indention
Cc: stable@vger.kernel.org
Signed-off-by: Corey Minyard <corey@minyard.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 97d35052a816875ad16bc37ae163ebc873b2928d)
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>

Author: cminyard

drivers/char/ipmi/ipmi_ssif.c

@@ -1888,6 +1888,7 @@ static int ssif_probe(struct i2c_client *client)
 					"kssif%4.4x", thread_num);
 	if (IS_ERR(ssif_info->thread)) {
 		rv = PTR_ERR(ssif_info->thread);
+		ssif_info->thread = NULL;
 		dev_notice(&ssif_info->client->dev,
 			   "Could not start kernel thread: error %d\n",
 			   rv);