Update iree-run-module to error out with more than one positional argument. (#6334)
Update iree-run-module to error out with more than one positional argument. (#6334)

Running `iree-run-module` with single dash flags are silently ignored while it waits to accept a module file via `stdin`. This leads to the program spinning endlessly without warning on inputs like:

```
./iree-run-module -module_file=/path/to/module.vmfb --entry_function=my_function --function_input=some_input ...
```

 `iree-run-module` doesn't consume positional arguments but single dash arguments are treated as such. This will prevent users from hitting confusing error cases with ignored flags. 

Adresses #5931
iree-org/iree,google/iree,iree-org/iree,google/iree,google/iree,iree-org/iree,google/iree,iree-org/iree,google/iree,iree-org/iree,google/iree,iree-org/iree,google/iree,iree-org/iree