add unaligned_store()

Don't know why I never wrote unaligned_store() to mirror
unaligned_load(), but now I have.  This replaces all
remaining memcpy() in SkJumper_stages.cpp, which is nice.

The generated stage code didn't change.

Change-Id: I714c1072a975d7fa268a4b06c13f06557bf0c12c
Reviewed-on: https://skia-review.googlesource.com/16870
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
2 files changed