Remove config.h from //webrtc:webrtc target.
Remove config.h from //webrtc:webrtc target.

It's already present in //webrtc:webrtc_common

BUG=webrtc:5878
NOTRY=True

Review-Url: https://codereview.webrtc.org/2854343002
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#17990}

ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc