ANDROID: netfilter: xt_qtaguid: xt_socket: build fixes

Add missing header <linux/miscdevice.h> and use
xt_socket_lookup_slow_v* instead of xt_socket_get*_sk
in xt_qtaguid.c.

Fix xt_socket_lookup_slow_v* functions in xt_socket.c
and declare them in xt_socket.h

Change-Id: I55819b2d4ffa82a2be20995c87d28fb5cc77b5ba
Signed-off-by: John Stultz <john.stultz@linaro.org>

[AmitP: Upstream commit 8db4c5be ("netfilter: move socket lookup
        infrastructure to nf_socket_ipv{4,6}.c")] moved socket lookup
        to nf_socket_ipv{4,6}.c, hence use nf_sk_lookup_slow_v[4|6]()
        instead of obsolete xt_socket_lookup_slow_v[4|6]().

        Also folded following android-4.9 commit changes into this patch
        7de1bb86dc5a ("ANDROID: netfilter: xt_qtaguid/socket: build fixes for 4.4")
        5b5ab94817f9 ("ANDROID: netfilter: xt_qtaguid: seq_printf fixes")]
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>