Revert "remove private copy of SkM44.h"

This reverts commit f8ef81b35e8f91360d034a5283052071c07f7d22.

Reason for revert: Build broken

Original change's description:
> remove private copy of SkM44.h
> 
> Change-Id: Ifd47b929bafd40d190722366a0c1e2b856220ab3
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/272836
> Reviewed-by: Florin Malita <fmalita@chromium.org>
> Commit-Queue: Mike Reed <reed@google.com>

TBR=fmalita@chromium.org,reed@google.com

Change-Id: I0da4ad43d5eaf5813ec489bc9117d4b8fc2b930e
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/273330
Reviewed-by: Julia Lavrova <jlavrova@google.com>
Commit-Queue: Julia Lavrova <jlavrova@google.com>
2 files changed