JIT: SVE cleanup - More SVE format merging

[TIHan]

Merges the following SVE formats:

case IF_SVE_EL_3A:   // ........xx.mmmmm ......nnnnnddddd -- SVE2 integer multiply-add long
        case IF_SVE_EN_3A:   // ........xx.mmmmm ......nnnnnddddd -- SVE2 saturating multiply-add interleaved long     
        case IF_SVE_EO_3A:   // ........xx.mmmmm ......nnnnnddddd -- SVE2 saturating multiply-add long
        case IF_SVE_FX_3A: // ........xx.mmmmm ......nnnnnddddd -- SVE2 integer absolute difference and accumulate long

case IF_SVE_FL_3A:   // ........xx.mmmmm ......nnnnnddddd -- SVE2 integer add/subtract long
        case IF_SVE_FN_3A:   // ........xx.mmmmm ......nnnnnddddd -- SVE2 integer multiply long
        case IF_SVE_FS_3A:   // ........xx.mmmmm ......nnnnnddddd -- SVE2 integer add/subtract interleaved long

[dotnet-policy-service]

Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch
See info in area-owners.md if you want to be subscribed.

[TIHan]

@kunalspathak @dotnet/arm64-contrib this is ready

[kunalspathak]

LGTM. Thanks!

[a74nh]

lgtm