gn path: Add missing newline to output summary

Before:
> Showing one of 92 "interesting" public paths.Use --all to print all paths.

After:
> Showing one of 92 "interesting" public paths.
> Use --all to print all paths.

Visual diff with full output: http://www.mergely.com/PJ83W4M7/

BUG=none
R=brettw@chromium.org

Review-Url: https://codereview.chromium.org/2807193004
Cr-Original-Commit-Position: refs/heads/master@{#465396}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: a38716a1806d8b03999d77f9bbfb1e793f60f34b
1 file changed
tree: ff7e9b17bd23de479cad03402111d697325e2b8a
  1. tools/