cmd/intarnal/obj: add new assembly format for VANDV and VANDB on loong64
In order to make it easier to write in assembly and to be consistent
with the usage of general instructions, a new assembly format is
added for the instructions VANDV and VANDB.
It also works for instructions XVAND{V,B}, [X]V{OR,XOR,NOR,ANDN,ORN}V
and [X]V{OR,XOR,NOR}B.
Change-Id: Ia75d607ac918950e58840ec627aaf0be45d837fe
Reviewed-on: https://go-review.googlesource.com/c/go/+/671316 Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Knyszek <mknyszek@google.com>