docs: add fuzz_function flag to the docs

Author: kyakdan

docs/fuzz-targets.md

@@ -167,8 +167,9 @@ flag, so that only the most important parameters are discussed here.
 | ----------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `<fuzzTarget>`                                                          | Import path to the fuzz target module.                                                                                                                                                                                                                                                                   |
 | `[corpus...]`                                                           | Paths to the corpus directories. If not given, no initial seeds are used nor interesting inputs saved.                                                                                                                                                                                                   |
-| `-- <fuzzingEngineFlags>`                                               | Parameters after `--` are forwarded to the internal fuzzing engine (`libFuzzer`). Available settings can be found in its [options documentation](https://www.llvm.org/docs/LibFuzzer.html#options).                                                                                                      |
+| `-f`, `--fuzz_function`                                                 | Name of the fuzz test entry point. It must be an exported function with a single [Buffer](https://nodejs.org/api/buffer.html) parameter. Default is `fuzz`.                                                                                                                                              |
 | `-i`, `--instrumentation_includes` / `-e`, `--instrumentation_excludes` | Part of filepath names to include/exclude in the instrumentation. A tailing `/` should be used to include directories and prevent confusion with filenames. `*` can be used to include all files. Can be specified multiple times. Default will include everything outside the `node_modules` directory. |
 | `--sync`                                                                | Enables synchronous fuzzing. **May only be used for entirely synchronous code**.                                                                                                                                                                                                                         |
 | `-h`, `--custom_hooks`                                                  | Filenames with custom hooks. Several hooks per file are possible. See further details in [docs/fuzz-settings.md](fuzz-settings.md).                                                                                                                                                                      |
 | `--help`                                                                | Detailed help message containing all flags.                                                                                                                                                                                                                                                              |
+| `-- <fuzzingEngineFlags>`                                               | Parameters after `--` are forwarded to the internal fuzzing engine (`libFuzzer`). Available settings can be found in its [options documentation](https://www.llvm.org/docs/LibFuzzer.html#options).                                                                                                      |