[PATCH 9/9] PKCS#7: Handle PKCS#7 messages that contain no X.509 certs

The X.509 certificate list in a PKCS#7 message is optional. To save space, we can omit the inclusion of any X.509 certificates if we are sure that we can look the relevant public key up by the serial number and issuer given in a signed info block. This also supports use of a signed info block

[PATCH 9/9] PKCS#7: Handle PKCS#7 messages that contain no X.509 certs

The X.509 certificate list in a PKCS#7 message is optional. To save space, we can omit the inclusion of any X.509 certificates if we are sure that we can look the relevant public key up by the serial number and issuer given in a signed info block. This also supports use of a signed info block