JIT SVE: Assertion failed '!"Got unexpected instruction format after MOVPRFX"' during 'Emit code'

[jakobbotsch]

// Generated by Fuzzlyn v2.3 on 2024-08-23 10:17:54
// Run on Arm64 Windows
// Seed: 14752078066107523191-vectort,vector64,vector128,armsve
// Reduced from 52.7 KiB to 0.7 KiB in 00:00:54
// Hits JIT assert in Release:
// Assertion failed '!"Got unexpected instruction format after MOVPRFX"' in 'Program:Main(Fuzzlyn.ExecutionServer.IRuntime)' during 'Emit code' (IL size 54; hash 0xade6b36b; FullOpts)
//
//     File: C:\dev\dotnet\runtime2\src\coreclr\jit\emitarm64sve.cpp Line: 18623
//
using System;
using System.Numerics;
using System.Runtime.Intrinsics;
using System.Runtime.Intrinsics.Arm;

public struct S2
{
    public Vector<int> F2;
}

public class Program
{
    public static S2 s_1;
    public static void Main()
    {
        var vr12 = Vector.Create<int>(0);
        var vr13 = Vector.Create<int>(0);
        var vr14 = M4();
        var vr15 = Vector128.CreateScalar(vr14).AsVector();
        var vr16 = Sve.AndAcross(vr13);
        s_1.F2 = Sve.ConditionalSelect(vr12, vr16, vr15);
    }

    public static int M4()
    {
        Vector<long> vr17 = default(Vector<long>);
        var vr11 = Vector.Create<long>(0);
        var vr8 = Sve.SubtractSaturate(vr17, vr11);
        return 1;
    }
}

cc @dotnet/arm64-contrib @dotnet/jit-contrib

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[a74nh]

I think this is the same underlying issue as #106872