fix continued expression indentation when cperl-indent-parens-as-block in effect

When cperl-indent-parens-as-block is in effect, expressions are indented incorrectly:

```
if ($var1 == 1 &&
      $var2 == 2 &&
      $var3 == 3) {
  ...
}
```

this patch fixes the indentation:

```
if ($var1 == 1 &&
    $var2 == 2 &&
    $var3 == 3) {
  ...
}
```

I'm working with this patch applied over one month and I didn't notice negative side effects.
Please test it and apply to upstream.