Fix compiler warnings for printfs with wrong-sized arguments.

We are printing word-sized values with %llX instead of %X which
causes compiler warnings, and causes us to print out incorrect
values as well.

Change-Id: Ibd889ca808e0e5a5abc813b453ae1abaac7514f4
Merge pull request #55 from awong-dev/warnings

Fix compiler warnings for printfs with wrong-sized arguments.