iftop: needs threads support

Fixes http://autobuild.buildroot.org/results/f2cb6113c360b8dbf63bafe5ae425921babdf636

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
libatasmart: move under libraries->hardware handling

It is a library, so it should go under libraries.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>