perf srcline: Fix memory leak in addr2inlines()

When libbfd is not used, addr2inlines() executes `addr2line -i` and
process output line by line.  But it resets filename to NULL in the loop
so getline() allocates additional memory everytime instead of realloc.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20171031020654.31163-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/srcline.c

@@ -456,20 +456,17 @@ static struct inline_node *addr2inlines(const char *dso_name, u64 addr,
 	while (getline(&filename, &len, fp) != -1) {
 		char *srcline;
 
-		if (filename_split(filename, &line_nr) != 1) {
-			free(filename);
+		if (filename_split(filename, &line_nr) != 1)
 			goto out;
-		}
 
 		srcline = srcline_from_fileline(filename, line_nr);
 		if (inline_list__append(sym, srcline, node) != 0)
 			goto out;
-
-		filename = NULL;
 	}
 
 out:
 	pclose(fp);
+	free(filename);
 
 	return node;
 }