ANDROID: GKI: remove netfilter apis from supported symbols

All of the required netfilter and fib functions should already be built
into the base GKI kernel, so nothing should need to be exported.  If
there are missing modules that are required for the base to work
properly, we can update the kernel configuration to properly refect that
instead of trying to support random filter modules.

Bug: 157965270
Cc: Liangcai Fan <liangcai.fan@unisoc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ia070ce5dc415d09b57e43e7a9ea6d9804ed2876b