Change am get-config command to use ABI string array

There is a list of supported ABIs in android.os.Build which
is ordered by preference. This is a more flexible list to use
instead of 2 fixed ABIs.

Change-Id: I6aa3b39b5ffa888ed83a870b937e18328dd6de39

cmds/am/src/com/android/commands/am/Am.java

@@ -44,6 +44,7 @@ import android.os.RemoteException;
 import android.os.ServiceManager;
 import android.os.SystemProperties;
 import android.os.UserHandle;
+import android.text.TextUtils;
 import android.util.AndroidException;
 import android.view.IWindowManager;
 import android.view.View;
@@ -1717,11 +1718,7 @@ public class Am extends BaseCommand {
             }
 
             System.out.println("config: " + Configuration.resourceQualifierString(config));
-            System.out.print("abi: " + Build.CPU_ABI);
-            if (!Build.CPU_ABI2.isEmpty()) {
-                System.out.print("," + Build.CPU_ABI2);
-            }
-            System.out.println();
+            System.out.println("abi: " + TextUtils.join(",", Build.SUPPORTED_ABIS));
 
         } catch (RemoteException e) {
         }