Driver Core: remove BUS_ID_SIZE

The name size limit is gone from the driver-core, this is
the removal of the last left-over.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

include/linux/device.h

@@ -25,8 +25,6 @@
 #include <asm/atomic.h>
 #include <asm/device.h>
 
-#define BUS_ID_SIZE		20
-
 struct device;
 struct device_private;
 struct device_driver;