Use _SC_NPROCESSORS_ONLN in Runtime.availableProcessors() API.

Bug: 130044127
Change-Id: I44f793d45aa6f1032d10060b7d60a761bd022bcc
diff --git a/ojluni/src/main/java/java/lang/Runtime.java b/ojluni/src/main/java/java/lang/Runtime.java
index acc75b0..862ff03 100644
--- a/ojluni/src/main/java/java/lang/Runtime.java
+++ b/ojluni/src/main/java/java/lang/Runtime.java
@@ -40,7 +40,7 @@
 import libcore.io.IoUtils;
 import libcore.io.Libcore;
 import libcore.util.EmptyArray;
-import static android.system.OsConstants._SC_NPROCESSORS_CONF;
+import static android.system.OsConstants._SC_NPROCESSORS_ONLN;
 
 /**
  * Every Java application has a single instance of class
@@ -708,7 +708,7 @@
      * @since 1.4
      */
     public int availableProcessors() {
-        return (int) Libcore.os.sysconf(_SC_NPROCESSORS_CONF);
+        return (int) Libcore.os.sysconf(_SC_NPROCESSORS_ONLN);
     }
 
     /**