Enable vectorized minmax_element using Neon on ARM64

[hazzlim]

Implement the namespace _Sorting algorithms using Neon, and enable _VECTORIZED_MINMAX_ELEMENT on ARM64 targets.

[hazzlim]

I have only enabled _VECTORIZED_MINMAX_ELEMENT in the first instance, as it seemed to make some sense to enable the other _Sorting algorithms in separate PRs.

This PR does not vectorize (u)int64_t on ARM64 as this was not faster than the scalar code.

The benchmark results are below:

Name	MSVC Speedup	Clang Speedup
bm<uint8_t, Op::Min>/8021	24.735	9.268
bm<uint8_t, Op::Min>/63	5.182	2.995
bm<uint8_t, Op::Max>/8021	24.695	9.561
bm<uint8_t, Op::Max>/63	4.896	2.976
bm<uint8_t, Op::Both>/8021	19.184	7.811
bm<uint8_t, Op::Both>/63	1.977	1.841
bm<uint16_t, Op::Min>/8021	12.053	4.524
bm<uint16_t, Op::Min>/31	3.052	2.089
bm<uint16_t, Op::Max>/8021	11.808	4.756
bm<uint16_t, Op::Max>/31	2.933	2.047
bm<uint16_t, Op::Both>/8021	5.426	4.052
bm<uint16_t, Op::Both>/31	1.413	1.521
bm<uint32_t, Op::Min>/8021	6.133	1.908
bm<uint32_t, Op::Min>/15	1.544	1.094
bm<uint32_t, Op::Max>/8021	6.074	1.92
bm<uint32_t, Op::Max>/15	1.53	1.132
bm<uint32_t, Op::Both>/8021	3.146	2.877
bm<uint32_t, Op::Both>/15	0.869	1.195
bm<int8_t, Op::Min>/8021	24.735	9.211
bm<int8_t, Op::Min>/63	5.222	2.778
bm<int8_t, Op::Max>/8021	25.244	9.286
bm<int8_t, Op::Max>/63	5.417	2.889
bm<int8_t, Op::Both>/8021	11.538	11.25
bm<int8_t, Op::Both>/63	1.989	1.76
bm<int16_t, Op::Min>/8021	11.953	4.667
bm<int16_t, Op::Min>/31	3.029	1.872
bm<int16_t, Op::Max>/8021	11.808	4.571
bm<int16_t, Op::Max>/31	3.123	1.882
bm<int16_t, Op::Both>/8021	6.582	5.729
bm<int16_t, Op::Both>/31	1.414	1.541
bm<int32_t, Op::Min>/8021	6.25	1.88
bm<int32_t, Op::Min>/15	1.6	1.135
bm<int32_t, Op::Max>/8021	6.133	1.867
bm<int32_t, Op::Max>/15	1.674	1.094
bm<int32_t, Op::Both>/8021	3.222	1.784
bm<int32_t, Op::Both>/15	0.877	0.903
bm<float, Op::Min>/8021	8.928	4.364
bm<float, Op::Min>/15	1.87	1.358
bm<float, Op::Max>/8021	9.111	4.267
bm<float, Op::Max>/15	2.062	1.371
bm<float, Op::Both>/8021	5.227	1.626
bm<float, Op::Both>/15	0.913	0.7
bm<double, Op::Min>/8021	4.426	2.029
bm<double, Op::Min>/7	0.929	0.731
bm<double, Op::Max>/8021	4.563	2.133
bm<double, Op::Max>/7	0.977	0.725
bm<double, Op::Both>/8021	2.583	0.786
bm<double, Op::Both>/7	0.445	0.402