Disable mac-host build for libbrillo. am: 5b67e34f82 am: 6942585b9d
am: c69cbeaaf3

Change-Id: I5dff0cadc40f617014ed4b5aff831c14584de26e
diff --git a/Android.bp b/Android.bp
index a25205b..efb7b68 100644
--- a/Android.bp
+++ b/Android.bp
@@ -148,6 +148,9 @@
         android: {
             srcs: libbrillo_linux_sources,
         },
+        darwin: {
+            enabled: false
+        }
     },
 }