Set apex_available property

The marked library(ies) were available to the APEXes via the hand-written
whitelist in build/soong/apex/apex.go. Trying to remove the whitelist
by adding apex_available property to the Android.bp of the libraries.

Exempt-From-Owner-Approval: cherry-pick from AOSP

Bug: 150999716
Test: m
Merged-In: I72fdff72790b1de7111d2fb74e54690795c7f1fc
(cherry picked from commit 6b158d3789561492b089c640c053bd242e1f34a4)
Change-Id: I72fdff72790b1de7111d2fb74e54690795c7f1fc
diff --git a/Android.bp b/Android.bp
index 5c52121..b809a9f 100644
--- a/Android.bp
+++ b/Android.bp
@@ -41,9 +41,8 @@
     host_supported: true,
     recovery_available: true,
     apex_available: [
-        "com.android.neuralnetworks",
-        "test_com.android.neuralnetworks",
         "//apex_available:platform",
+        "//apex_available:anyapex",
     ],
     native_bridge_supported: true,
 }