bpfdomain: attribute for domain which can use BPF

Require all domains which can be used for BPF to be marked as
bpfdomain, and add a restriction for these domains to not
be able to use net_raw or net_admin. We want to make sure the
network stack has exclusive access to certain BPF attach
points.

Bug: 140330870
Bug: 162057235
Test: build (compile-time neverallows)
Change-Id: I29100e48a757fdcf600931d5eb42988101275325
diff --git a/private/bpfloader.te b/private/bpfloader.te
index 3fbc8dc..7644cac 100644
--- a/private/bpfloader.te
+++ b/private/bpfloader.te
@@ -1,5 +1,7 @@
 type bpfloader_exec, system_file_type, exec_type, file_type;
 
+typeattribute bpfloader bpfdomain;
+
 # allow bpfloader to write to the kernel log (starts early)
 allow bpfloader kmsg_device:chr_file w_file_perms;