[make] Add libFuzzer support

This CL introduces the make rules needed to build libFuzzer fuzz
targets. These targets are ignored unless USE_ASAN=1 is specified.

SEC-43 #comment Adds minimal Zircon support

Test: Manually tested with HID parser fuzzer

Change-Id: I139f40800e2e41ad6906dab2816a0d2e3047cd4c