[PATCH] uml: use variables rather than symlinks in dependencies

Use explicit os-...  in make dependencies instead of playing with symlinks
(symlink in question is still created - it's needed for other things; however,
there's no reason to complicate ordering here).

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>