perf bpf filter: Fix a broken perf sample data naming for BPF CO-RE

BPF CO-RE requires 3 underscores for the ignored suffix rule but it
mistakenly used only 2.  Let's fix it.

Fixes: 3a8b8fc3 ("perf bpf filter: Support pre-5.16 kernels where 'mem_hops' isn't in 'union perf_mem_data_src'")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230525000307.3202449-1-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/bpf_skel/sample_filter.bpf.c

@@ -25,7 +25,7 @@ struct perf_sample_data___new {
 } __attribute__((preserve_access_index));
 
 /* new kernel perf_mem_data_src definition */
-union perf_mem_data_src__new {
+union perf_mem_data_src___new {
 	__u64 val;
 	struct {
 		__u64   mem_op:5,	/* type of opcode */
@@ -108,7 +108,7 @@ static inline __u64 perf_get_sample(struct bpf_perf_event_data_kern *kctx,
 		if (entry->part == 7)
 			return kctx->data->data_src.mem_blk;
 		if (entry->part == 8) {
-			union perf_mem_data_src__new *data = (void *)&kctx->data->data_src;
+			union perf_mem_data_src___new *data = (void *)&kctx->data->data_src;
 
 			if (bpf_core_field_exists(data->mem_hops))
 				return data->mem_hops;