driver core: class: Remove needless return in void API class_remove_file()

Remove return since both class_remove_file() and class_remove_file_ns()
are void functions.

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

include/linux/device/class.h

···
 static inline void class_remove_file(const struct class *class,
 				     const struct class_attribute *attr)
 {
-	return class_remove_file_ns(class, attr, NULL);
+	class_remove_file_ns(class, attr, NULL);
 }
 
 /* Simple class attribute that is just a static string */