Disable libbinder darwin builds

libbinder makes heavy use of linux headers, so it won't build on a mac.
This gives us cleaner errors when a mac target depends on it. Instead of
seeing libbinder build breakages, we will see the missing dependency
error.

Exempt-From-Owner-Approval: fixing build breakage

Test: none
Bug: 172023026
Change-Id: I4eadf2c9c09599b5d1bcafdb7d8559946c854e49
diff --git a/libs/binderthreadstate/Android.bp b/libs/binderthreadstate/Android.bp
index 88752ee..08c62df 100644
--- a/libs/binderthreadstate/Android.bp
+++ b/libs/binderthreadstate/Android.bp
@@ -19,6 +19,11 @@
     double_loadable: true,
     vendor_available: true,
     host_supported: true,
+    target: {
+        darwin: {
+            enabled: false,
+        }
+    },
 
     shared_libs: [
         "libbinder",