Specifying SRG and PP for ROADM-to-ROADM service

When requesting a ROADM-to-ROADM service (from SRG PP to SRG PP) using the OpenROADM service API, the PCE just selects the first available SRG and PP on the end nodes. It would be nice if it were possible to specify which SRG and PP to provision. According to the org-openroadm-common-service-types yang module, the endpoint port attribute in the service-create RPC input uniquely identifies the termination point (port-device-name + port-circuit-pack-name + port-name) so it should be possible to specify SRG and PP but this information is currently not taken into account by TransportPCE.