clk: pxa: add a check for the return value of kzalloc()

kzalloc() is a memory allocation function which can return NULL when
some internal memory errors happen. So it is better to check it to
prevent potential wrong memory access.
Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
Link: https://lore.kernel.org/r/tencent_2B9817738F38B02844C245946EFF3B407E09@qq.comSigned-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/pxa/clk-pxa.c

@@ -104,6 +104,8 @@ int __init clk_pxa_cken_init(const struct desc_clk_cken *clks,
 
 	for (i = 0; i < nb_clks; i++) {
 		pxa_clk = kzalloc(sizeof(*pxa_clk), GFP_KERNEL);
+		if (!pxa_clk)
+			return -ENOMEM;
 		pxa_clk->is_in_low_power = clks[i].is_in_low_power;
 		pxa_clk->lp = clks[i].lp;
 		pxa_clk->hp = clks[i].hp;