Update SkOpts namespaces.

src/opts/SkOpts_sse41.cpp

Index: src/opts/SkOpts_sse41.cpp
diff --git a/src/opts/SkOpts_sse41.cpp b/src/opts/SkOpts_sse41.cpp
index 938b2f9e83462c46c51a3c0ba56492446a44d6cc..bbb77e3b8d5233a094b679f99acf827905b5521b 100644
--- a/src/opts/SkOpts_sse41.cpp
+++ b/src/opts/SkOpts_sse41.cpp
@@ -7,13 +7,13 @@
 
 #include "SkOpts.h"
 
-#define SK_OPTS_NS sse41
+#define SK_OPTS_NS sk_sse41
 #include "SkBlurImageFilter_opts.h"
 
 namespace SkOpts {
     void Init_sse41() {
-        box_blur_xx = sse41::box_blur_xx;
-        box_blur_xy = sse41::box_blur_xy;
-        box_blur_yx = sse41::box_blur_yx;
+        box_blur_xx = sk_sse41::box_blur_xx;
+        box_blur_xy = sk_sse41::box_blur_xy;
+        box_blur_yx = sk_sse41::box_blur_yx;
     }
 }