When adding paths to the round-robin path selector, their order gets inverted,
which is not desirable.
Fix by replacing list_add() with list_add_tail().
Signed-off-by: Jonathan E Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: <dm-devel@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>