init: remove restorecon() from util.cpp

restorecon() has become nothing more than a small wrapper around
selinux_android_restore().  This itself isn't super problematic, but
it is an obstacle for compiling util.cpp on the host as that function
is not available on the host.

Bug: 36970783
Test: Boot bullhead
Change-Id: I7e209ece6898f9a0d5eb9e5d5d8155c2f1ba9faf
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 27b72f9..1eacb36 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -762,7 +762,7 @@
             }
         } else {
             in_flags = false;
-            if (restorecon(args[i].c_str(), flag) < 0) {
+            if (selinux_android_restorecon(args[i].c_str(), flag) < 0) {
                 ret = -errno;
             }
         }