DL Node Sync Procedure

Following tasks are performed:

1. Created a TAPA task for NFAPI P7 Clock. Since in NFAPI, VNF/DU will not receive any SLOT.ind for every slot from PNF/PHY thus separate CLOCK is required at VNF to track the SLOT/SFN and Delay Management PRocedure (SYnching Procedure Section 2.1.3.2, SCF225)       

   • https://gerrit.o-ran-sc.org/r/c/o-du/l2/+/12934   << Gerrit for P7 Clock

2. Changed the name of the function "fapiSlotInd" to "procMacSlotInd" as now Slot ind can be received from FAPI and in NFAPI case as well

   • https://gerrit.o-ran-sc.org/r/c/o-du/l2/+/12934   << Gerrit for P7 Clock

3. Basic Utils Functions like Filling and extraction of P7Hdr and Calculate NextSlot and otther coversion functions like sfn_slot to time and vice versa

4. Building and Handling of DL NODE SYNC

5. Added a "SPkPostS32" which adds Signed 32 int in the post of msgBuffer. this will be used to pack delta_sfnSlot while building DL NODE SYNC in VNF(or DU)

6. Put all the nfapi related files(all .c) in NFAPI_ENABLED flag so that it doesnt get compiled when NFAPI is not enabled.

7. Add the clock generation at PNF side

•  Gerrit Pts 3 to 8 - https://gerrit.o-ran-sc.org/r/c/o-du/l2/+/12958