tls: Drop local code to add hash OID, let kernel do it

Drop tls.c code to build the PKCS#1 DigestInfo structure which basically
consisted of prepending the signature hash algorithm's OID to the hash.
Let the key API do it by setting the hash type in the l_key_sign and
l_key_verify calls.  Slightly simplify the tls_rsa_sign and
tls_rsa_verify code while doing this.
1 file changed