MD Settings: Fix broken regulatory label in About on Samus

BUG=546841
R=dpapad@chromium.org
TEST=put something in /usr/share/chromeos-assets/regulatory_labels/us/label.{png,txt}
     or test on a samus
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:closure_compilation
NOPRESUBMIT=true # unrelated html errors, will fix later

Review-Url: https://codereview.chromium.org/2094703005
Cr-Commit-Position: refs/heads/master@{#402337}
3 files changed