From: "Randy.Dunlap" <rddunlap@osdl.org>, Will Dyson <will_dyson@pobox.com>, me

Add generic filesystem options parser (infrastructure) and use it to parse
mount options in several filesystems (adfs, affs, autofs, autofs4, ext2,
ext3, fat, hfs, hpfs, isofs, jfs, procfs, udf, and ufs).

It saves between 128 and 512 bytes per filesystem.