[eclipse] Set the "ignore warnings".

Set the ignore optional warning flag on the source folders that are
containing generated sources.

Signed-off-by: Stéphane Galland <galland@arakhne.org>
[m2e] Set "ignore warnings".

Set the ignore optional warning flag on the source folders that are
containing generated sources.

Signed-off-by: Stéphane Galland <galland@arakhne.org>