Defines starting with `b' in bsd/dev

• BAD_BLK_OFF bsd/dev/disk.h:90
• _BSD_DEV_DISK_ bsd/dev/disk.h:60
• _BSD_DEV_DISK_LABEL_ bsd/dev/disk_label.h:32
• _BSD_DEV_KMREG_COM_ bsd/dev/kmreg_com.h:34
• _BSD_DEV_LDD_PRIV_ bsd/dev/ldd.h:41
• _BUSVAR_ bsd/dev/busvar.h:33