perf tools: Make decompress_to_file() function static

There's no outside user of it.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index 8ee1faa..9f4b72d 100644
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -239,7 +239,7 @@
 	return m.kmod;
 }
 
-bool decompress_to_file(const char *ext, const char *filename, int output_fd)
+static bool decompress_to_file(const char *ext, const char *filename, int output_fd)
 {
 	unsigned i;
 
diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
index ef69de2..e1adadd 100644
--- a/tools/perf/util/dso.h
+++ b/tools/perf/util/dso.h
@@ -252,7 +252,6 @@
 				   char *root_dir, char *filename, size_t size);
 bool is_supported_compression(const char *ext);
 bool is_kernel_module(const char *pathname, int cpumode);
-bool decompress_to_file(const char *ext, const char *filename, int output_fd);
 bool dso__needs_decompress(struct dso *dso);
 int dso__decompress_kmodule_fd(struct dso *dso, const char *name);
 int dso__decompress_kmodule_path(struct dso *dso, const char *name,