mfd: Declare abx500_remove_ops()

Otherwise sparse warns about a public symbol with no declaration and
the compiler can't spot if the callers and users have different signatures
for the function.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/include/linux/mfd/abx500.h b/include/linux/mfd/abx500.h
index be7373c..67bd6f7 100644
--- a/include/linux/mfd/abx500.h
+++ b/include/linux/mfd/abx500.h
@@ -229,4 +229,5 @@
 };
 
 int abx500_register_ops(struct device *core_dev, struct abx500_ops *ops);
+void abx500_remove_ops(struct device *dev);
 #endif