Fix output path of run_sksllex to match what the script does

This doesn't get rid of the warning about multiple rules, but it does
ensure the build reaches steady state (after two runs).

Change-Id: I9a90b8e310225fb5cab544a86dd271162d0fe0df
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/372122
Auto-Submit: Brian Osman <brianosman@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
1 file changed