clk: socfpga: allow for multiple parents on Arria10 periph clocks

There are some Arria10 clocks of type "altr,socfpga-a10-perip-clk" that can
have multiple parents. Fix up the __socfpga_periph_init() to call
of_clk_parent_fill() that will return the appropriate number of parents.

Also, update __socfpga_gate_init() to call of_clk_parent_fill() helper
function.

Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/socfpga/clk-gate-a10.c

@@ -115,7 +115,6 @@ static void __init __socfpga_gate_init(struct device_node *node,
 	const char *parent_name[SOCFPGA_MAX_PARENTS];
 	struct clk_init_data init;
 	int rc;
-	int i = 0;
 
 	socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
 	if (WARN_ON(!socfpga_clk))
@@ -167,12 +166,9 @@ static void __init __socfpga_gate_init(struct device_node *node,
 	init.name = clk_name;
 	init.ops = ops;
 	init.flags = 0;
-	while (i < SOCFPGA_MAX_PARENTS && (parent_name[i] =
-			of_clk_get_parent_name(node, i)) != NULL)
-		i++;
 
+	init.num_parents = of_clk_parent_fill(node, parent_name, SOCFPGA_MAX_PARENTS);
 	init.parent_names = parent_name;
-	init.num_parents = i;
 	socfpga_clk->hw.hw.init = &init;
 
 	clk = clk_register(NULL, &socfpga_clk->hw.hw);