dependencies.sh: stop mixing echo and printf (use echo)

'printf' was introduced because it is more portable than 'echo -e'. But
when the escape sequences are just newlines we can just as well use
plain 'echo' (and remove the newline escape sequences).

This looks cleaner than having some lines with echo and some with
printf.

Signed-off-by: Bjørn Forsman <bjorn.forsman@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>