[STM32F4xx] update of STM32CubeF4 to version 1.5 - part 3

Adaption of gpio_api to new hal version: register to set/clear a pin is
now a single 32bit register

Author: ohagendorf

libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/gpio_api.c

@@ -55,10 +55,9 @@ void gpio_init(gpio_t *obj, PinName pin)
     GPIO_TypeDef *gpio = (GPIO_TypeDef *)gpio_add;
 
     // Fill GPIO object structure for future use
-    obj->mask    = gpio_set(pin);
-    obj->reg_in  = &gpio->IDR;
-    obj->reg_set = &gpio->BSRRL;
-    obj->reg_clr = &gpio->BSRRH;
+    obj->mask        = gpio_set(pin);
+    obj->reg_in      = &gpio->IDR;
+    obj->reg_set_clr = &gpio->BSRR;
 }
 
 void gpio_mode(gpio_t *obj, PinMode mode)

libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/gpio_object.h

@@ -44,17 +44,16 @@ typedef struct {
     PinName  pin;
     uint32_t mask;
     __IO uint32_t *reg_in;
-    __IO uint16_t *reg_set;
-    __IO uint16_t *reg_clr;
+    __IO uint32_t *reg_set_clr;
 } gpio_t;
 
 static inline void gpio_write(gpio_t *obj, int value)
 {
     MBED_ASSERT(obj->pin != (PinName)NC);
     if (value) {
-        *obj->reg_set = obj->mask;
+        *obj->reg_set_clr = obj->mask;
     } else {
-        *obj->reg_clr = obj->mask;
+        *obj->reg_set_clr = obj->mask << 16;
     }
 }