Torpedo mainboard changes to fix warnings.

Fixes the warnings generated in the torpedo mainboard build.  Most of these
changes are similar to fixes already implemented in the persimmon mainboard.

Change-Id: Ib931be51c0e6448c00c8cfeb13073e1f392582a5
Signed-off-by: Martin L Roth <martin@se-eng.com>
Signed-off-by: Marc Jones <marcj303@gmail.com>
Reviewed-on: http://review.coreboot.org/634
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>