Switch to libkeyutils.

Bug: http://b/37991155
Test: builds+boots
Change-Id: Iba763eccc0768f58ce7b51d861f13e51d91ec382
diff --git a/ext4_utils/Android.bp b/ext4_utils/Android.bp
index a2987aa..493fae5 100644
--- a/ext4_utils/Android.bp
+++ b/ext4_utils/Android.bp
@@ -41,11 +41,11 @@
 
         android: {
             srcs: [
-                "key_control.cpp",
                 "ext4_crypt.cpp",
             ],
             shared_libs: [
                 "libbase",
+                "libkeyutils",
                 "libselinux",
             ],