Remove unused variables in BitcoinMiner/RandomXMiner which saves about 3.5KB of memory per mining thread

src/miner.cpp

@@ -1270,7 +1270,6 @@ void static RandomXMiner()
             LogPrintf("Running HushRandomXMiner with %u transactions in block (%u bytes)\n",pblock->vtx.size(),::GetSerializeSize(*pblock,SER_NETWORK,PROTOCOL_VERSION));
 
             // Search
-            uint8_t pubkeys[66][33]; arith_uint256 bnMaxPoSdiff; uint32_t blocktimes[66]; int mids[256],nonzpkeys,i,j,externalflag;
             uint32_t savebits;
             int64_t nStart = GetTime();
             pblock->nBits  = GetNextWorkRequired(pindexPrev, pblock, Params().GetConsensus());
@@ -1617,7 +1616,7 @@ void static BitcoinMiner()
             LogPrintf("Running HushMiner.%s with %u transactions in block (%u bytes)\n",solver.c_str(),pblock->vtx.size(),::GetSerializeSize(*pblock,SER_NETWORK,PROTOCOL_VERSION));
 
             // Search
-            uint8_t pubkeys[66][33]; arith_uint256 bnMaxPoSdiff; uint32_t blocktimes[66]; int mids[256],nonzpkeys,i,j,externalflag; uint32_t savebits; int64_t nStart = GetTime();
+            uint32_t savebits; int64_t nStart = GetTime();
             pblock->nBits         = GetNextWorkRequired(pindexPrev, pblock, Params().GetConsensus());
             savebits = pblock->nBits;
             HASHTarget = arith_uint256().SetCompact(savebits);