SLH-DSA and LMS support

[jo-bitsch]

Describe the feature
PKCS#11v3.2 has support for both SLH-DSA (a.k.a FIPS 205) as well as LMS/HSS RFC8554.

OpenSSL also supports both of these via the provider interface (see oqs-provider)

Being able to use SLH-DSA or LMS provided by a PKCS11 library would be great.

Expected behavior
SLH-DSA and LMS based private keys residing in a PKCS11 accessible interface are accessible in OpenSSL via the pkcs11-provider in exactly the same way that e.g. ML-DSA based keys are.

Additional context
none