o net/ipv4/af_inet.c: remove include seq_file.h and proc_fs.h, not needed anymore

thanks to Chris Wilson <chris@qwirx.com> for pointing out that seq_file.h
was not needed anymore.

net/ipv4/af_inet.c

@@ -103,8 +103,6 @@
 #include <net/tcp.h>
 #include <net/udp.h>
 #include <linux/skbuff.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
 #include <net/sock.h>
 #include <net/raw.h>
 #include <net/icmp.h>