Fix error codes.
(cherry picked from commit 388aff08dc38d6e4c5146d445b62f581bb484ed4)
Add function CMS_RecipientInfo_encrypt

Add CMS_RecipientInfo_encrypt: this function encrypts an existing content
encryption key to match the key in the RecipientInfo structure: this is
useful if a new recpient is added to and existing enveloped data structure.

Add documentation.
(cherry picked from commit e1f1d28f34cc5cfc87772e0d8331e00137a4a213)