STM32 F3: Fix a couple of new warnings noted in build testing. There are more new warnings, but I think these may be due to improper default values for some configuration settings. I have not looked into this in detail.

arch/arm/src/stm32/stm32_hrtim.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/stm32/stm32_hrtim.c
  *
- *   Copyright (C) 2017 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2017-2018 Gregory Nutt. All rights reserved.
  *   Author: Mateusz Szafoni <raiden00@railab.me>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -3605,6 +3605,7 @@ static uint16_t hrtim_deadtime_get(FAR struct hrtim_dev_s *dev, uint8_t timer,
                                    uint8_t dt)
 {
 #warning missing logic
+  return 0;
 }
 
 /****************************************************************************

configs/stm32f334-disco/src/stm32_smps.c

@@ -382,7 +382,7 @@ static int smps_setup(FAR struct smps_dev_s *dev)
 
   /* TODO: create current limit table */
 
-errout:
+  UNUSED(priv);
   return OK;
 }