rtc: simplified /proc/driver/rtc handling

This simplifies the RTC procfs support by removing the class_interface that
hooks it into the rtc core.  If it's configured, then sysfs support is now
part of the RTC core, and is never a separate module.

It also removes the class_interface hook, now that its last remaining user is
gone.  (That API is usable only with a "struct class_device".)

It's another step towards being able to remove "struct class_device".

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-By: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-core.h

@@ -1,5 +1,3 @@
-extern int rtc_interface_register(struct class_interface *intf);
-
 #ifdef CONFIG_RTC_INTF_DEV
 
 extern void __init rtc_dev_init(void);
@@ -16,6 +14,18 @@ extern void rtc_dev_del_device(struct rtc_device *rtc);
 
 #endif
 
+#ifdef CONFIG_RTC_INTF_PROC
+
+void rtc_proc_add_device(struct rtc_device *rtc);
+void rtc_proc_del_device(struct rtc_device *rtc);
+
+#else
+
+#define rtc_proc_add_device(r)	do{}while(0)
+#define rtc_proc_del_device(r)	do{}while(0)
+
+#endif
+
 #ifdef CONFIG_RTC_INTF_SYSFS
 
 extern void __init rtc_sysfs_init(struct class *);