net: bcmgenet: Do not return from void function

A stray return was added in the macro bcmgenet_##name##_writel where it
should not, drop it.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 69d2ea9c ("net: bcmgenet: Use correct I/O accessors")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/genet/bcmgenet.h

@@ -684,7 +684,7 @@ static inline void bcmgenet_##name##_writel(struct bcmgenet_priv *priv,	\
 					u32 val, u32 off)		\
 {									\
 	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)) \
-		return __raw_writel(val, priv->base + offset + off);	\
+		__raw_writel(val, priv->base + offset + off);		\
 	else								\
 		writel_relaxed(val, priv->base + offset + off);		\
 }