nFAPI time conversion: handle numerologies flexibly

At both the PNF and the VNF, introduce a separate numerology field, and
pass the numerology when converting time information using macros from
nfapi_interface.h. The actually numerology is still hardcoded to 1 (as it
was before), but the follow-up commits will put a suitable numerology.

In both cases, but the numerology next to the frame/slot information.

nfapi/open-nFAPI/vnf/inc/vnf_p7.h

@@ -91,6 +91,8 @@ typedef struct nfapi_vnf_p7_connection_info {
 	int sfn_sf;
 	int sfn;
 	int slot;
+  int mu; // some 5G slot calculations need the numerology to know the number
+          // of slots
 
 	int socket;
 	struct sockaddr_in local_addr;