Macros starting with `d' in ufs

• dblksize ufs/fs.h:424
• dbtofsb ufs/fs.h:335
• DFASTLINK ufs/dinode.h:106
• DIRSIZ ufs/dir.h:81
• dkminor ufs/ufs_disksubr.c:150
• dkpart ufs/ufs_disksubr.c:149
• dkunit ufs/ufs_disksubr.c:148
• DQREF ufs/quota.h:169
• dtog ufs/fs.h:365
• dtogd ufs/fs.h:366