net: sockets: tls: Support for DER cert chain and NOCOPY optimisation

Add TLS socket option "TLS_CERT_NOCOPY" to prevent the copy of
certificates to mbedTLS heap if possible.

Add support to provide a chain of DER certificates by registering
them with multiple tags.

Signed-off-by: Lucas Dietrich <ld.adecy@gmail.com>
2 files changed