hvc_console: display printk messages on console.

printk only works for "registered consoles."  Currently, the hvc_console
code calls register_console() from hvc_instantiate(), but that's only
used in the early console case.  In hvc_alloc(), register_console() was
not called.

Add a call to register_console() in hvc_alloc(), set up the index in
the hvc_console, and set up the necessary vtermnos[] and cons_op[]
entries so that printk functions work.
Signed-off-by: NMiche Baker-Harvey <miche@google.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/tty/hvc/hvc_console.c

@@ -852,7 +852,7 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
 	 * find index to use:
 	 * see if this vterm id matches one registered for console.
 	 */
-	for (i=0; i < MAX_NR_HVC_CONSOLES; i++)
+	for (i = 0; i < MAX_NR_HVC_CONSOLES; i++)
 		if (vtermnos[i] == hp->vtermno &&
 		    cons_ops[i] == hp->ops)
 			break;
@@ -862,9 +862,13 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
 		i = ++last_hvc;
 
 	hp->index = i;
+	hvc_console.index = i;
+	vtermnos[i] = vtermno;
+	cons_ops[i] = ops;
 
 	list_add_tail(&(hp->next), &hvc_structs);
 	spin_unlock(&hvc_structs_lock);
+	register_console(&hvc_console);
 
 	return hp;
 }
@@ -875,6 +879,7 @@ int hvc_remove(struct hvc_struct *hp)
 	unsigned long flags;
 	struct tty_struct *tty;
 
+	unregister_console(&hvc_console);
 	spin_lock_irqsave(&hp->lock, flags);
 	tty = tty_kref_get(hp->tty);