remove unused DXDY SSSE3 bitmap opts

Just a buncha dead code.  These are only hooked up via
opts_check_x86.cpp, which only ever looks at the _DX_ procs.

Change-Id: Ifb366b0fbf17e97d46ebb53c69ac3efa9101df9d
Reviewed-on: https://skia-review.googlesource.com/c/170760
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
3 files changed