Macros starting with `d' in ufs

• dblksize ufs/fs.h:420
• dbtofsb ufs/fs.h:331
• DIRSIZ ufs/dir.h:80
• dkminor ufs/ufs_disksubr.c:241
• dkpart ufs/ufs_disksubr.c:240
• dkunit ufs/ufs_disksubr.c:239
• DQREF ufs/quota.h:168
• dtog ufs/fs.h:361
• dtogd ufs/fs.h:362