Android doesn't have cache data in sysfs

Summary: Since sysfs doesn't have cache information for the CPU on Android guard this on Android

Reviewed By: yfeldblum

Differential Revision: D7051199

fbshipit-source-id: 20fcfa91aa2f642c6cab33b0fb55f121b609d58f

folly/concurrency/CacheLocality.cpp

@@ -34,13 +34,13 @@ namespace folly {
 
 /// Returns the best real CacheLocality information available
 static CacheLocality getSystemLocalityInfo() {
-#ifdef __linux__
-  try {
-    return CacheLocality::readFromSysfs();
-  } catch (...) {
-    // keep trying
+  if (kIsLinux) {
+    try {
+      return CacheLocality::readFromSysfs();
+    } catch (...) {
+      // keep trying
+    }
   }
-#endif
 
   long numCpus = sysconf(_SC_NPROCESSORS_CONF);
   if (numCpus <= 0) {