disable SkOpts on x86 iOS (simulator)

TBR=

BUG=skia:

Review URL: https://codereview.chromium.org/1266443006
diff --git a/src/core/SkOpts.cpp b/src/core/SkOpts.cpp
index c833f19..9ccc66d 100644
--- a/src/core/SkOpts.cpp
+++ b/src/core/SkOpts.cpp
@@ -55,7 +55,8 @@
     //TODO: _dsp2, _armv7, _armv8, _x86, _x86_64, _sse42, _avx, avx2, ... ?
 
     static void init() {
-    #if defined(SK_CPU_X86)
+        // TODO: Chrome's not linking _sse* opts on iOS simulator builds.  Bug or feature?
+    #if defined(SK_CPU_X86) && !defined(SK_BUILD_FOR_IOS)
         uint32_t abcd[] = {0,0,0,0};
         cpuid(abcd);
         if (abcd[3] & (1<<26)) { Init_sse2(); }