clocksource/drivers/ingenic: Fix section mismatch

The function ingenic_tcu_get_clock() is annotated for the __init
section but it is actually called from the online cpu callback.

That will lead to a crash if a CPU is hotplugged after boot time.

Remove the __init annotation for the ingenic_tcu_get_clock()
function.

Fixes: f19d838d08fc (clocksource/drivers/ingenic: Add high resolution timer support for SMP/SMT)
Reported-by: kernel test robot <[e-mail]>
Signed-off-by: Daniel Lezcano <[e-mail]>
Reviewed-by: Paul Cercueil <[e-mail]>
Tested-by: 周琰杰 (Zhou Yanjie) <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/clocksource/ingenic-timer.c

···
 	return IRQ_HANDLED;
 }
 
-static struct clk * __init ingenic_tcu_get_clock(struct device_node *np, int id)
+static struct clk *ingenic_tcu_get_clock(struct device_node *np, int id)
 {
 	struct of_phandle_args args;