net: sfp: fix sfp_bus_put() kernel documentation

The kbuild test robot found a problem with htmldocs with the recent
change to the SFP interfaces.  Fix the kernel documentation for
sfp_bus_put() which was missing an '@' before the argument name
description.

Fixes: 727b366 ("net: sfp: rework upstream interface")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/sfp-bus.c

@@ -331,7 +331,7 @@ static void sfp_bus_release(struct kref *kref)
 
 /**
  * sfp_bus_put() - put a reference on the &struct sfp_bus
- * bus: the &struct sfp_bus found via sfp_bus_find_fwnode()
+ * @bus: the &struct sfp_bus found via sfp_bus_find_fwnode()
  *
  * Put a reference on the &struct sfp_bus and free the underlying structure
  * if this was the last reference.