firewire: replace tricky statement by two simple ones

struct fw_driver::remove returns void, still the comma expression's value
is zero. This is harder to parse than necessary, so replace the single
expression by two easier ones.

Signed-off-by: Uwe Kleine-König <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/firewire/core-device.c

···
 	struct fw_driver *driver =
 			container_of(dev->driver, struct fw_driver, driver);
 
-	return driver->remove(fw_unit(dev)), 0;
+	driver->remove(fw_unit(dev));
+
+	return 0;
 }
 
 static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)