Remove incorrect cast to AsyncSocketAdapter.
Remove incorrect cast to AsyncSocketAdapter.

socket_ in OpenSSLAdapter should be (and is in tests) an AsyncSocket but
doesn't have to be an AsyncSocketAdapter. In tests this is
rtc::VirtualSocket which is an rtc::AsyncSocket. This also matches the
BIO_new_socket type signature.

This fixes the remaining UBSan vptr bot errors.

BUG=webrtc:5124, webrtc:5226
R=tommi@webrtc.org, torbjorng@webrtc.org

Review URL: https://codereview.webrtc.org/1639883002 .

Cr-Original-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#11391}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 0b518bf6fcf87b652546a232a6ea8e53c6c4d316

Alkalyne/webrtctrunk,jchavanton/webrtc,Alkalyne/webrtctrunk,jchavanton/webrtc,jchavanton/webrtc,jchavanton/webrtc,jchavanton/webrtc,jchavanton/webrtc,Alkalyne/webrtctrunk,Alkalyne/webrtctrunk,Alkalyne/webrtctrunk,Alkalyne/webrtctrunk,Alkalyne/webrtctrunk,jchavanton/webrtc,Alkalyne/webrtctrunk