crypto/internal/nistec: drop endianness swap assembly
It has negligible performance impact now that we have compiler
intrinsics, and removing it helps slightly narrow the gap between
the assembly and Go implementations.
Change-Id: Ia02807a973b567952c659bb4868632a73ff3c143
Reviewed-on: https://go-review.googlesource.com/c/go/+/627939 Reviewed-by: Russ Cox <rsc@golang.org>
Auto-Submit: Filippo Valsorda <filippo@golang.org> Reviewed-by: Daniel McCarney <daniel@binaryparadox.net> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>