In case of TLS 1.3 and hybrid TLS 1.2/1.3, propose
PKCS1 v1.5 signatures with SHA_384/512 not only
SHA_256. There is no point in not proposing them
if they are available.
In TLS 1.3 those could be useful for certificate
signature verification.
In hybrid TLS 1.2/1.3 this allows to propose for
TLS 1.2 the same set of signature algorithms.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>