ANDROID: selinux: Fix Android specific configs handling in policydb_write()

Commit 6ea234c and fac0755 implements Android specific bits
for RTM_GETLINK and RTM_GETNEIGH{TBL}, but they are not
considered into policydb_write() function. As a result, if userspace
wants to dump /sys/fs/selinux/policy, kernel won't pass those bits
in config, and userspace cannot get correct config bits of loaded
policy. Fix it, similar to mls bits handling.

Fixes: 6ea234c74a60 ("ANDROID: selinux: modify RTM_GETLINK permission")
Fixes: fac07550bdac ("ANDROID: selinux: modify RTM_GETNEIGH{TBL}")
Change-Id: I9602fd7cfe2eefc0cbd79b96892369bd5d4af15d
Signed-off-by: Wang Han <wanghan1995315@gmail.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>