This moves rms_level.* into a separate build target.
Bug: webrtc:11226
Change-Id: I94ceacd1ec65dda48f5d19b22ba2625d13543e08
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/170323
Reviewed-by: Per Åhgren <peah@webrtc.org>
Commit-Queue: Sam Zackrisson <saza@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30856}