[llvm] [X86][AVX] Add missing X86ISD::VBROADCAST(v2i64 -> v4i64) isel pattern for AVX1 targets (PR #102853)

[Mészáros Gergely via llvm-commits]

Maetveis wrote:

> Does the v4i32 -> v8i32 equivalent broadcast pattern occur as well?

I couldn't produce it by changing the types in the IR: https://godbolt.org/z/6nTPjhsqf

https://github.com/llvm/llvm-project/pull/102853