Switch to toybox getenforce/setenforce.

Change-Id: I1f11c231633dd443c13d099c27b0823b3082ed58
diff --git a/Android.mk b/Android.mk
index 8911e6c..5deaadf 100644
--- a/Android.mk
+++ b/Android.mk
@@ -222,6 +222,7 @@
     fgrep \
     find \
     free \
+    getenforce \
     groups \
     head \
     hostname \
@@ -260,6 +261,7 @@
     rmdir \
     rmmod \
     seq \
+    setenforce \
     setsid \
     sha1sum \
     sleep \