staging: iio: compress return logic

Simplify function returns by merging assignment and return.
Found with Coccinelle.

Semantic patch:
@@
local idexpression ret;
expression e;
@@

-ret =
+return
     e;
-return ret;
Signed-off-by: Gargi Sharma <gs051095@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/staging/iio/meter/ade7854.c

@@ -426,9 +426,7 @@ static int ade7854_set_irq(struct device *dev, bool enable)
 	else
 		irqen &= ~BIT(17);
 
-	ret = st->write_reg_32(dev, ADE7854_MASK0, irqen);
-
-	return ret;
+	return st->write_reg_32(dev, ADE7854_MASK0, irqen);
 }
 
 static int ade7854_initial_setup(struct iio_dev *indio_dev)