Add Content Type OID for id-ct-rpkiSignedPrefixList

Add Content Type OID for id-ct-rpkiSignedPrefixList

References: draft-ietf-sidrops-rpki-prefixlist
Title: "A profile for Signed Prefix Lists for Use in the Resource Public Key Infrastructure (RPKI)"

OID assigned under 'SMI Security for S/MIME CMS Content Type (1.2.840.113549.1.9.16.1)'
https://www.iana.org/assignments/smi-numbers/smi-numbers.xhtml#security-smime-1

Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/23426)