clk: mmp: pxa168: fix return value check in pxa168_clk_init()

Fix the retrn value check which testing the wrong variable
in pxa168_clk_init().

Fixes: ab08aefcd12d ("clk: mmp: add pxa168 DT support for clock driver")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
diff --git a/drivers/clk/mmp/clk-of-pxa168.c b/drivers/clk/mmp/clk-of-pxa168.c
index 87f2317..f110c02 100644
--- a/drivers/clk/mmp/clk-of-pxa168.c
+++ b/drivers/clk/mmp/clk-of-pxa168.c
@@ -262,7 +262,7 @@ static void __init pxa168_clk_init(struct device_node *np)
 	}
 
 	pxa_unit->apmu_base = of_iomap(np, 1);
-	if (!pxa_unit->mpmu_base) {
+	if (!pxa_unit->apmu_base) {
 		pr_err("failed to map apmu registers\n");
 		return;
 	}