test/fuzz/llvm: Simplify parallel execution logic

	local testn=$1    # Number of test to run in parallel

	local fuzz_num=$2 # Number of fuzzer tests

	local time=$3     # Time available for all fuzzers

	local testn_idx idx

	local core

	local pid

	# Calculate time for a single test and multiply it by number

	# of test execute in parallel and round it up to 1 sek per test

	timen=$(printf %d $(((time / fuzz_num) * testn)))

	timen=$((timen == 0 ? 1 : timen))

	for ((i = 0; i < fuzz_num; i++)); do

		core=$(printf "0x%x" $((0x1 << (i % testn))))

		start_llvm_fuzz $i $timen $core &> $output_dir/llvm/llvm_"$FUZZER"_$i.txt &

	for ((i = 0; i < fuzz_num; i += testn)); do

		idx=-1 pids=()

		# Run max up to $testn tests in parallel ...

		while ((testn_idx = i + ++idx, testn_idx < fuzz_num && idx < testn)); do

			core=$(printf "0x%x" $((0x1 << idx)))

			start_llvm_fuzz $testn_idx $timen $core &> "$output_dir/llvm/llvm_${FUZZER}_${testn_idx}.txt" &

			pids+=($!)

		# Wait for processes to finish

		if (((i + 1) % testn == 0 || fuzz_num - i - 1 == 0)); then

			(

				sleep $((timen * 10 + 100))

				echo "Timeout $time"

				exit 1

			) &

			timeout_pid=$!

		done

		# ... and now wait for them

		for pid in "${pids[@]}"; do

				wait $pid

			wait "$pid"

		done

			kill $timeout_pid || :

			pids=()

		fi

		# queue up another $testn bundle at next iteration

	done

}