net/irda: sh_sir: fix return value check in sh_sir_set_baudrate()

In case of error, the function clk_get() returns ERR_PTR()
and never returns NULL pointer. The NULL test in the error
handling should be replaced with IS_ERR().

dpatch engine is used to auto generated this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/irda/sh_sir.c

@@ -280,7 +280,7 @@ static int sh_sir_set_baudrate(struct sh_sir_self *self, u32 baudrate)
 	}
 
 	clk = clk_get(NULL, "irda_clk");
-	if (!clk) {
+	if (IS_ERR(clk)) {
 		dev_err(dev, "can not get irda_clk\n");
 		return -EIO;
 	}