lenovo: Don't use extern with functions

Change-Id: I8313ba1d93922297e5061701dad47d07617d1dcd
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/17804
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
diff --git a/src/mainboard/lenovo/x60/dock.h b/src/mainboard/lenovo/x60/dock.h
index ef8a977..a8911dd 100644
--- a/src/mainboard/lenovo/x60/dock.h
+++ b/src/mainboard/lenovo/x60/dock.h
@@ -16,9 +16,9 @@
 #ifndef THINKPAD_X60_DOCK_H
 #define THINKPAD_X60_DOCK_H
 
-extern int dock_connect(void);
-extern void dock_disconnect(void);
-extern int dock_present(void);
-extern int dlpc_init(void);
-extern int dock_ultrabay_device_present(void);
+int dock_connect(void);
+void dock_disconnect(void);
+int dock_present(void);
+int dlpc_init(void);
+int dock_ultrabay_device_present(void);
 #endif