Error checking for randomx vm creation

src/miner.cpp

@@ -1175,6 +1175,10 @@ void static RandomXMiner()
                 // TODO: use correct variables
                 randomx_init_cache(randomxCache, &randomxKey, sizeof randomxKey);
                 randomx_vm *myVM = randomx_create_vm(flags, randomxCache, NULL);
+                if(myVM == NULL) {
+                    LogPrintf("Cannot create RandomX VM, aborting!\n");
+                    return;
+                }
 
                 randomx_calculate_hash(myVM, &randomxInput, sizeof randomxInput, randomxHash);