Rewrite compression and group checks.

Replace existing compression and groups check with two functions.

tls1_check_pkey_comp() checks a keys compression algorithms is consistent
with extensions.

tls1_check_group_id() checks is a group is consistent with extensions
and preferences.

Rename tls1_ec_nid2curve_id() to tls1_nid2group_id() and make it static.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/=4412)