Increase ring-buffer size even more

It seems, the most complex API, dfa-reporting, requires
an even higher value.

Reproduce this with
```
make dfareporting2d1-cli-cargo ARGS="build --no-default-features --features=with-syntex"
```

syntex_syntax/src/print/pp.rs

@@ -163,9 +163,9 @@ pub struct PrintStackElem {
 const SIZE_INFINITY: isize = 0xffff;
 
 pub fn mk_printer<'a>(out: Box<io::Write+'a>, linewidth: usize) -> Printer<'a> {
-    // Yes 10, it makes the ring buffers big enough to never
+    // Yes 55, it makes the ring buffers big enough to never
     // fall behind.
-    let n: usize = 10 * linewidth;
+    let n: usize = 55 * linewidth;
     debug!("mk_printer {}", linewidth);
     let token = vec![Token::Eof; n];
     let size = vec![0; n];