Enable `-Wredundant-parens`
Enable `-Wredundant-parens`

Warn on redundant parentheses in declarators whose parsing might not match
the user intent, e.g.
```
root [0] int i = 1;
root [1] (bool)i
(bool) true
root [2] bool(i)
ROOT_prompt_1:1:5: warning: redundant parentheses surrounding declarator [-Wredundant-parens]
bool(i)
    ^~~
(bool) false
```

For more information see http://github.com/root-project/issues/8304.
Closes issue #8304.

root-mirror/cling,root-mirror/cling,root-mirror/cling,root-mirror/cling,root-mirror/cling,root-mirror/cling