Consider supporting new syntax of --module-source-path

[JEP 261 defines syntax](https://openjdk.org/jeps/261#Compile-time) for `--module-source-path` which is out of sync with what javac actually supports, see https://docs.oracle.com/en/java/javase/23/docs/specs/man/javac.html#the-module-source-path-option

See in particular this variant:
```
--module-source-path module-name=file-path (path-separator file-path)*
```

Should ecj support the same syntax options?