Extend TLS 1.3 signature table.

Add additional entries in the TLS 1.2 signature table to include
the name, sig and hash NID (if any) and required curve (if any).

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2301)