Fix precompiled_sepolicy neverallow flag

Because we should ignore neverallow when SELINUX_IGNORE_NEVERALLOWS is
true.

Test: add a fake rule and build with/without SELINUX_IGNORE_NEVERALLOWS
Change-Id: I7811f5cef2243dae5b5de1154a36ab167871dc4f
diff --git a/Android.bp b/Android.bp
index 0b9aa98..21916b8 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1236,9 +1236,6 @@
         },
         IS_TARGET_MIXED_SEPOLICY: {
             ignore_neverallow: true,
-            conditions_default: {
-                ignore_neverallow: false,
-            },
         },
         MIXED_SEPOLICY_VERSION: {
             srcs: [