clocksource/drivers/timer-econet-en751221: Fix clock reference leak

timer_init() obtains the timer clock with of_clk_get() and only reads
its frequency with clk_get_rate(); the clock is never prepared nor
enabled. All four return paths after the acquisition (of_iomap()
failure, clocksource_mmio_init() failure, cevt_init() failure and
success) return without clk_put(), leaking the consumer reference.

Drop the reference with clk_put() right after the frequency has been
read. The clock enable state is untouched.

Fixes: 3b4c33ac87 ("clocksource/drivers: Add EcoNet Timer HPT driver")
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Signed-off-by: Daniel Lezcano <daniel.lezcano@kernel.org>
Tested-by: Caleb James DeLisle <cjd@cjdns.fr>
Link: https://patch.msgid.link/20260915054552.1729612-1-vulab@iscas.ac.cn

drivers/clocksource/timer-econet-en751221.c

@@ -181,6 +181,7 @@ static int __init timer_init(struct device_node *np)
 	}
 
 	econet_timer.freq_hz = clk_get_rate(clk);
+	clk_put(clk);
 
 	for (int i = 0; i < num_blocks; i++) {
 		econet_timer.membase[i] = of_iomap(np, i);