perf build: Properly guard libbpf includes

Including libbpf header files should be guarded by HAVE_LIBBPF_SUPPORT.
In bpf_counter.h, move the skeleton utilities under HAVE_BPF_SKEL.

Fixes: d6a735ef32 ("perf bpf_counter: Move common functions to bpf_counter.h")
Reported-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Mike Leach <mike.leach@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20230105172243.7238-1-mike.leach@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-trace.c

@@ -16,7 +16,9 @@
 
 #include "util/record.h"
 #include <api/fs/tracing_path.h>
+#ifdef HAVE_LIBBPF_SUPPORT
 #include <bpf/bpf.h>
+#endif
 #include "util/bpf_map.h"
 #include "util/rlimit.h"
 #include "builtin.h"

tools/perf/util/bpf_counter.h

@@ -4,9 +4,12 @@
 
 #include <linux/list.h>
 #include <sys/resource.h>
+
+#ifdef HAVE_LIBBPF_SUPPORT
 #include <bpf/bpf.h>
 #include <bpf/btf.h>
 #include <bpf/libbpf.h>
+#endif
 
 struct evsel;
 struct target;
@@ -87,6 +90,8 @@ static inline void set_max_rlimit(void)
 	setrlimit(RLIMIT_MEMLOCK, &rinf);
 }
 
+#ifdef HAVE_BPF_SKEL
+
 static inline __u32 bpf_link_get_id(int fd)
 {
 	struct bpf_link_info link_info = { .id = 0, };
@@ -127,5 +132,6 @@ static inline int bperf_trigger_reading(int prog_fd, int cpu)
 
 	return bpf_prog_test_run_opts(prog_fd, &opts);
 }
+#endif /* HAVE_BPF_SKEL */
 
 #endif /* __PERF_BPF_COUNTER_H */