Switch to toybox ls.

Change-Id: I8c34fbd8d9b004f52ec8ed882603e3dc1935b001
diff --git a/Android.mk b/Android.mk
index fa54f05..b653ecf 100644
--- a/Android.mk
+++ b/Android.mk
@@ -215,7 +215,7 @@
 
 LOCAL_MODULE := toybox
 
-# dupes: dd df du ls mount renice
+# dupes: dd df du mount renice
 # useless?: freeramdisk fsfreeze install makedevs mkfifo nbd-client
 #           partprobe pivot_root pwdx rev rfkill switch_root tty vconfig
 # prefer BSD netcat instead?: nc netcat
@@ -268,6 +268,7 @@
     ln \
     logname \
     losetup \
+    ls \
     lsmod \
     lsusb \
     md5sum \