Fix a double-free that can occur because memory ownership of rootKeyPair and hostKeyPair and transferred to the rootEVP and hostEVP structures by EVP_PKEY_assign().
blah
Initialize structure to NULL to retrieve pubkey
Don't release passed parameter, owned by the caller
Merge branch 'ssl-doublefree-fix' into pairing-material-test

* ssl-doublefree-fix:
  Don't release passed parameter, owned by the caller
  Initialize structure to NULL to retrieve pubkey
  Fix a double-free that can occur because memory ownership of rootKeyPair and hostKeyPair and transferred to the rootEVP and hostEVP structures by EVP_PKEY_assign().