Variables starting with `d' in bsd/hfs

• d bsd/hfs/hfs.h:500
• Delete bsd/hfs/hfs_vfsutils.c:656
• dInstErr bsd/hfs/hfs_macos_defs.h:612
• doclusterread bsd/hfs/hfs_readwrite.c:94
• doclusterwrite bsd/hfs/hfs_readwrite.c:95
• dtReserved bsd/hfs/hfs_macos_defs.h:823