Try again to put SkXfermode_opts in SK_OPTS_NS

src/opts/SkOpts_ssse3.cpp

Index: src/opts/SkOpts_ssse3.cpp
diff --git a/src/opts/SkOpts_ssse3.cpp b/src/opts/SkOpts_ssse3.cpp
index 35f74e143b7b9f968b6d54e504cf28930a9c19a1..675cdaa23e44bb832f99a7ef967cefb5c6356640 100644
--- a/src/opts/SkOpts_ssse3.cpp
+++ b/src/opts/SkOpts_ssse3.cpp
@@ -13,7 +13,7 @@
 
 namespace SkOpts {
     void Init_ssse3() {
-        create_xfermode = SkCreate4pxXfermode;
+        create_xfermode = sk_ssse3::create_xfermode;
         blit_mask_d32_a8 = sk_ssse3::blit_mask_d32_a8;
         color_cube_filter_span = sk_ssse3::color_cube_filter_span;
     }