atm: lanai: Remove in_interrupt() usage

lanai_shutdown_tx_vci() uses in_interrupt() to issue a warning message
if the function was used in context in which it is not safe to sleep.

The usage of in_interrupt() in driver code is deprecated as it can not always
detect all states where it is not allowed to sleep.

msleep() has debug code which will trigger a warning if used in bad
context.

Remove in_interrupt().

Cc: Chas Williams <3chas3@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/atm/lanai.c

@@ -765,8 +765,7 @@ static void lanai_shutdown_tx_vci(struct lanai_dev *lanai,
 	struct sk_buff *skb;
 	unsigned long flags, timeout;
 	int read, write, lastread = -1;
-	APRINTK(!in_interrupt(),
-	    "lanai_shutdown_tx_vci called w/o process context!\n");
+
 	if (lvcc->vbase == NULL)	/* We were never bound to a VCI */
 		return;
 	/* 15.2.1 - wait for queue to drain */