selftests/bpf: fix bpf_get_current_task

Fix bpf_get_current_task() declaration.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/testing/selftests/bpf/bpf_helpers.h

@@ -278,7 +278,7 @@ static int (*bpf_skb_change_type)(void *ctx, __u32 type) =
 	(void *) BPF_FUNC_skb_change_type;
 static unsigned int (*bpf_get_hash_recalc)(void *ctx) =
 	(void *) BPF_FUNC_get_hash_recalc;
-static unsigned long long (*bpf_get_current_task)(void *ctx) =
+static unsigned long long (*bpf_get_current_task)(void) =
 	(void *) BPF_FUNC_get_current_task;
 static int (*bpf_skb_change_tail)(void *ctx, __u32 len, __u64 flags) =
 	(void *) BPF_FUNC_skb_change_tail;