sysemu: drop register_devices from header

No user in sight.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-id: 20130430094149.GA29094@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

include/sysemu/sysemu.h

@@ -176,8 +176,6 @@ void usb_info(Monitor *mon, const QDict *qdict);
 
 void rtc_change_mon_event(struct tm *tm);
 
-void register_devices(void);
-
 void add_boot_device_path(int32_t bootindex, DeviceState *dev,
                           const char *suffix);
 char *get_boot_devices_list(size_t *size);