When enforcing Ignition+TurboFan for a function literal during
AstNumbering, make sure to print the bailout reason with --trace-opt
to make it easier to figure out what caused the bailout.

BUG=chromium:670691
R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2550093002
Cr-Commit-Position: refs/heads/master@{#41472}