init: Fix -DUSER_MODE_LINUX compilation

Bug: 64985489
Test: Manual

Change-Id: Ib37d2b9affe500b66b9243fb24a7dee23b7730f2
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
diff --git a/init/Android.bp b/init/Android.bp
index b1f0279..efa5a02 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -54,6 +54,9 @@
                 "-DSHUTDOWN_ZERO_TIMEOUT=1",
             ],
         },
+        uml: {
+            cppflags: ["-DUSER_MODE_LINUX"],
+        }
     },
 }