perf tools: move perf_pmus__find_core_pmu() prototype to pmus.h

perf_pmus__find_core_pmu() is implemented in util/pmus.c but its
prototpye is in util/pmu.h. Move it to util/pmus.h.

Suggested-by: Ian Rogers <[e-mail]>
Signed-off-by: Thomas Falcon <[e-mail]>
Reviewed-by: Ian Rogers <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Namhyung Kim <[e-mail]>

tools/perf/util/pmu.h

···
 				  bool eager_load);
 struct perf_pmu *perf_pmu__create_placeholder_core_pmu(struct list_head *core_pmus);
 void perf_pmu__delete(struct perf_pmu *pmu);
-struct perf_pmu *perf_pmus__find_core_pmu(void);
 
 const char *perf_pmu__name_from_config(struct perf_pmu *pmu, u64 config);
 bool perf_pmu__is_fake(const struct perf_pmu *pmu);

tools/perf/util/pmus.h

···
 					       const char *sysfs_name,
 					       const char *name);
 struct perf_pmu *perf_pmus__fake_pmu(void);
+struct perf_pmu *perf_pmus__find_core_pmu(void);
 
 #endif /* __PMUS_H */