AGC2 flags: remove deprecated fields.
AGC2 flags: remove deprecated fields.

Downstream projects adapted, clean up.

Bug: webrtc:7494
Change-Id: I019b8dd79c6bc55c900fb5595d5e2ee8aa0a2400
Reviewed-on: https://webrtc-review.googlesource.com/c/110865
Commit-Queue: Alessio Bazzica <eed802d553432598d8dd1392efc4d65b5eefde4d@webrtc.org>
Reviewed-by: Alex Loiko <999d0b481e5703ad7006f0848e249f8b2c3f29bd@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#25656}
TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc