Removed usage of BMI2 pdep with SSE2 alternative

[gfoidl]

Description

Replaced Bmi2.ParallelBitDeposit with SSE2 alternative.

• Perf-win on Intel (see benchmark results)
• Bmi2 pdep has bad perf on AMD, so this issue can be sailed around
• SSE2 has broader support than BMI2

Addresses #18949

Benchmarks

Code
For the benchmarks the vectorized path are disabled, so only sequential processing is performed, to have better figures for replacing BMI2. With the vectorized path only the "remainder" is processed by BMI2, so the gain won't be as huge.

I don't have access to any AMD machine, so can't run a benchmark for this.
But according to the results from the runtime-repo for a similar change, this should be a huge boost for AMD-machines.

BenchmarkDotNet=v0.12.0, OS=Windows 10.0.18362
Intel Core i7-7700HQ CPU 2.80GHz (Kaby Lake), 1 CPU, 8 logical and 4 physical cores
.NET Core SDK=5.0.100-alpha1-015774
  [Host]     : .NET Core 3.1.1 (CoreCLR 4.700.19.60701, CoreFX 4.700.19.60801), X64 RyuJIT
  DefaultJob : .NET Core 3.1.1 (CoreCLR 4.700.19.60701, CoreFX 4.700.19.60801), X64 RyuJIT

Method	BytesLen	Mean	Error	StdDev	Ratio	RatioSD
Current_master	4	6.431 ns	0.1013 ns	0.0846 ns	1.00	0.00
This_PR	4	5.083 ns	0.0531 ns	0.0471 ns	0.79	0.01
Current_master	8	5.446 ns	0.0757 ns	0.0671 ns	1.00	0.00
This_PR	8	5.071 ns	0.0529 ns	0.0495 ns	0.93	0.01
Current_master	16	7.341 ns	0.1798 ns	0.1766 ns	1.00	0.00
This_PR	16	6.341 ns	0.1068 ns	0.0999 ns	0.86	0.03
Current_master	32	10.612 ns	0.0405 ns	0.0379 ns	1.00	0.00
This_PR	32	8.439 ns	0.0964 ns	0.0902 ns	0.80	0.01
Current_master	100	26.499 ns	0.2693 ns	0.2519 ns	1.00	0.00
This_PR	100	18.494 ns	0.1560 ns	0.1459 ns	0.70	0.01

[gfoidl]

This didn't inline always in some constellations. So I'll force the JIT to do so 😉

[ghost]

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