clk: fix return value check in bcm2835_init_clocks()

In case of error, the function clk_register_fixed_rate() returns
ERR_PTR() and never returns NULL. The NULL test in the return value
check should be replaced with IS_ERR().

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

drivers/clk/clk-bcm2835.c

@@ -33,17 +33,17 @@ void __init bcm2835_init_clocks(void)
 
 	clk = clk_register_fixed_rate(NULL, "sys_pclk", NULL, CLK_IS_ROOT,
 					250000000);
-	if (!clk)
+	if (IS_ERR(clk))
 		pr_err("sys_pclk not registered\n");
 
 	clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT,
 					126000000);
-	if (!clk)
+	if (IS_ERR(clk))
 		pr_err("apb_pclk not registered\n");
 
 	clk = clk_register_fixed_rate(NULL, "uart0_pclk", NULL, CLK_IS_ROOT,
 					3000000);
-	if (!clk)
+	if (IS_ERR(clk))
 		pr_err("uart0_pclk not registered\n");
 	ret = clk_register_clkdev(clk, NULL, "20201000.uart");
 	if (ret)
@@ -51,7 +51,7 @@ void __init bcm2835_init_clocks(void)
 
 	clk = clk_register_fixed_rate(NULL, "uart1_pclk", NULL, CLK_IS_ROOT,
 					125000000);
-	if (!clk)
+	if (IS_ERR(clk))
 		pr_err("uart1_pclk not registered\n");
 	ret = clk_register_clkdev(clk, NULL, "20215000.uart");
 	if (ret)