api/go1.16: remove crypto/tls APIs that are moved to Go 1.17

api/go1.16: remove crypto/tls APIs that are moved to Go 1.17

CL 269697 was created before CL 276454 and submitted after,
so the api/go1.16.txt file needs to be updated accordingly
to fix the build.

Updates #32406.

Change-Id: I6bf79cc981be504e0baefa82982814aaee4434dc
Reviewed-on: https://go-review.googlesource.com/c/go/+/278992
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Trust: Katie Hockman <katie@golang.org>
Reviewed-by: Katie Hockman <katie@golang.org>