[Bug target/86896] invalid vmovdqa64 instruction for KNL emitted

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86896

--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> ---
Fixed on trunk in r260969 which is a front-end change. Thus I'm going to
isolate a smaller test-case first.