Support draft-kwiatkowski-tls-ecdhe-mlkem and draft-tls-westerbaan-xyber768d00

This commit adds support for the three code points in draft-kwiatkowski-tls-ecdhe-mlkem and the code point 0x6399 from draft-tls-westerbaan-xyber768d00. The group 0x6399 uses a pre-standard version of Kyber and is considered obsolete.

Author: David Cooper

etc/curves-mapping.txt

@@ -45,3 +45,7 @@
       0x01,0x02 -   ffdhe4096   ffdhe4096
       0x01,0x03 -   ffdhe6144   ffdhe6144
       0x01,0x04 -   ffdhe8192   ffdhe8192
+      0x11,0xeb -   SecP256r1MLKEM768  SecP256r1MLKEM768
+      0x11,0xec -   X25519MLKEM768  X25519MLKEM768
+      0x11,0xed -   SecP384r1MLKEM1024  SecP384r1MLKEM1024
+      0x63,0x99 -   X25519Kyber768Draft00  X25519Kyber768Draft00