misc: update ignored files

The place where toolchains were built has moved
from targets/ to .build/

We still ignore the old target/ dir, as users may have
samples that still use that location.

Also, reorder the ignore paterns.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

reporter_name="YEM"

reporter_url="http://ymorin.is-a-geek.org/"

reporter_comment=""