These are where the DTLS- and TLS-specific transport layer hooks will be
defined. Later we can probably move much of the implementations of these
hooks into these files so those functions can be static.
While I'm here, fix up the naming of some constants.
Change-Id: I1009dd9fdc3cc4fd49fbff0802f6289931abec3d
Reviewed-on: https://boringssl-review.googlesource.com/8665
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>