Update SkMatrix to use skvx instead of SkNx

Change-Id: I012ea84083a592d7d2303067128857c01cd770dd
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/541176
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
3 files changed