Sepolicy for rw mount point for product extensions.

Bug: 110808288
Test: device boots with /mnt/product present and selinux label
      mnt_product_file applied correctly.

Change-Id: I596e4b79285fe1a79d31ad1b07f4bcffe6a6cd98
diff --git a/private/file_contexts b/private/file_contexts
index bec6b14..9f3d817 100644
--- a/private/file_contexts
+++ b/private/file_contexts
@@ -541,4 +541,8 @@
 
 #############################
 # mount point for read-write vendor partitions
-/mnt/vendor(/.*)?          u:object_r:mnt_vendor_file:s0
+/mnt/vendor(/.*)?           u:object_r:mnt_vendor_file:s0
+
+#############################
+# mount point for read-write product partitions
+/mnt/product(/.*)?          u:object_r:mnt_product_file:s0