clk: gpio-gate: Don't export __init functions

This function is marked as __init, so exposing it to modules
doesn't make any sense and it isn't used by modules anyway.

drivers/clk/clk-gpio-gate.c:192:13: warning: symbol 'of_gpio_gate_clk_setup' was not declared. Should it be static?

Cc: Jyri Sarha <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/clk-gpio-gate.c

···
 /**
  * of_gpio_gate_clk_setup() - Setup function for gpio controlled clock
  */
-void __init of_gpio_gate_clk_setup(struct device_node *node)
+static void __init of_gpio_gate_clk_setup(struct device_node *node)
 {
 	struct clk_gpio_gate_delayed_register_data *data;
 
···
 
 	of_clk_add_provider(node, of_clk_gpio_gate_delayed_register_get, data);
 }
-EXPORT_SYMBOL_GPL(of_gpio_gate_clk_setup);
 CLK_OF_DECLARE(gpio_gate_clk, "gpio-gate-clock", of_gpio_gate_clk_setup);
 #endif