utils, debug: refactor not needed variable

Issue namhyung#1553 related ret variable dead store clean up.

Not needed initialization on double variable.

Signed-off-by: Paran Lee <p4ranlee@gmail.com>

utils/debug.c

@@ -383,7 +383,7 @@ void print_time_unit(uint64_t delta_nsec)
 
 void print_diff_percent(uint64_t base_nsec, uint64_t pair_nsec)
 {
-	double percent = 999.99;
+	double percent;
 	const char *sc = get_color(COLOR_CODE_NORMAL);
 	const char *ec = get_color(COLOR_CODE_RESET);
 

utils/kernel.c

@@ -54,7 +54,6 @@ struct kfilter {
 static int set_filter_file(const char *filter_file, struct list_head *filters)
 {
 	struct kfilter *pos, *tmp;
-	int ret = -1;
 	int fd;
 
 	fd = open_tracing_file(filter_file, true);
@@ -75,10 +74,9 @@ static int set_filter_file(const char *filter_file, struct list_head *filters)
 		if (write(fd, " ", 1) != 1)
 			pr_dbg2("writing filter file failed, but ignoring...\n");
 	}
-	ret = 0;
 
 	close(fd);
-	return ret;
+	return 0;
 }
 
 static int set_tracing_filter(struct uftrace_kernel_writer *kernel)