Referring to https://github.com/google/oss-fuzz/issues/7575, if the
fuzzer suffix contains periods, it can cause ClusterFuzz to misinterpret
the file extension of the fuzzer executables and thus misidentify them.
Otherwise, the targets will require libstdc++, the i386 version of which
is not available in the OSS-Fuzz runtime environment. The OSS-Fuzz
build environment passes -stdlib:libc++ in the CXXFLAGS environment
variable in order to mitigate this issue, since the runtime environment
has the i386 version of libc++, but using that compiler flag requires
using the C++ compiler.
This commit integrates OSS-Fuzz targets directly into the libjpeg-turbo
source tree, thus obsoleting and improving code coverage relative to
Google's OSS-Fuzz target for libjpeg-turbo (previously available here:
https://github.com/google/oss-fuzz).
I hope to eventually create fuzz targets for the BMP, GIF, and PPM
readers as well, which would allow for fuzz-testing compression, but
since those readers all require an input file, it is unclear how to
build an efficient fuzzer around them. It doesn't make sense to
fuzz-test compression in isolation, because compression can't accept
arbitrary input data.
