[SVE][CodeGen] Lower SDIV & UDIV to SVE intrinsics

Summary:
This patch maps IR operations for sdiv & udiv to the
@llvm.aarch64.sve.[s|u]div intrinsics.

A ptrue must be created during lowering as the div instructions
have only a predicated form.

Patch contains changes by Andrzej Warzynski.

Reviewers: sdesmalen, c-rhodes, efriedma, cameron.mcinally, rengolin

Reviewed By: efriedma

Subscribers: tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, andwar, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78569