Remove unnecessary code in the commit of "Fix: RPR for JVET_Z0054_BLK_REF_PIC_REORDER".
During the fix for RPR for JVET-Z0054, RPR handling was added in ARMC functions adjustMergeCandidatesInOneCandidateGroup() and adjustMergeCandidates() for the fix. However, it's later found out that it's not necessary. And according to the meeting note, RPR handling in ARMC was not agreed and was encouraged for further study.