Add a fuzz target to test DNG image parsing in dng_sdk.

This fuzz target aims at `dng_read_image::ReadLosslessJPEG` to do
variant analysis for CVE-2020-9589 (b/156261521).

Test: # To run fuzzer on the host do:
Test: source build/envsetup.sh && \
Test: lunch aosp_x86_64-eng && \
Test: SANITIZE_HOST=address make dng_parser_fuzzer && \
Test: LD_LIBRARY_PATH=out/host/linux-x86/fuzz/x86_64/lib/ \
Test: out/host/linux-x86/fuzz/x86_64/dng_parser_fuzzer/dng_parser_fuzzer
Change-Id: I2f71abbbc97e35a409a3843c7c4462d6e5c40ee5
5 files changed