This commit only adds the bare minimum to get the new library building
through GN, the actual content of row_sve.cc is empty for now until we
start porting some kernels across.
Bug: libyuv:973
Change-Id: Ibdf4fc258761f3e507d700f27a405099c667ac75
Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/5424738
Reviewed-by: Frank Barchard <fbarchard@chromium.org>
