bpf: Remove duplicate headers

Remove duplicate headers which are included twice.
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200908132201.184005-1-chenzhou10@huawei.com

net/core/bpf_sk_storage.c

@@ -12,7 +12,6 @@
 #include <net/sock.h>
 #include <uapi/linux/sock_diag.h>
 #include <uapi/linux/btf.h>
-#include <linux/btf_ids.h>
 
 DEFINE_BPF_STORAGE_CACHE(sk_cache);