jkummerow made many changes to wasm-compiler.cc and co, and is
more than qualified to be an owner.

R=clemensb@chromium.org

Change-Id: I05cb1b7c73627d4c3fe59f154c1267c7cd44a2d8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2307314Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68946}