staging: kpc2000: kpc_spi: Remove unnecessary null check before kfree

A null check before a kfree is redundant, so remove it.
This is detected by coccinelle.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190711140726.46732-1-yuehaibing@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/kpc2000/kpc2000_spi.c

@@ -412,8 +412,7 @@ kp_spi_cleanup(struct spi_device *spidev)
 {
 	struct kp_spi_controller_state *cs = spidev->controller_state;
 
-	if (cs)
-		kfree(cs);
+	kfree(cs);
 }
 
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