coreboot/util/fuzz-tests

Fuzz tests
==========
make run (with afl-fuzz installed) takes a real long time and creates test
cases in jpeg-results/ that crash the jpeg code.

These test cases can then be used to gdb the test app and dig into the
decoder to fix the issues.

This is mostly a proof of concept because the jpeg code isn't used very often
(only for splash screens). However there are other regions in coreboot that
could benefit from similar treatment.