[PATCH] udf: fix uid/gid options and add uid/gid=ignore and forget options

[PATCH] udf: fix uid/gid options and add uid/gid=ignore and forget options

As Pekka Enberg pointed out, with the if still following the else, you can
still get a null uid written to the disk if you specify a default uid= without
uid=forget.  In other words, if the desktop user is uid=1000 and the mount
option uid=1000 is given ( which is done on ubuntu automatically and probably
other distributions that use hal ), then if any other user besides uid 1000
owns a file then a 0 will be written to the media as the owning uid instead.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>