[ext][stm32] update libopencm3

to get updates from libopencm3 and remove our own workarounds for:
- STM32F4 25Mhz clock: https://github.com/libopencm3/libopencm3/pull/311
- STM32 defines for TIM9-TIM17: https://github.com/libopencm3/libopencm3/pull/350
- STM32 set I2C address: https://github.com/libopencm3/libopencm3/pull/344

additionally get fixes:
- STM32 safe gpio toggle: https://github.com/libopencm3/libopencm3/pull/337

sw/airborne/arch/stm32/mcu_arch.c

@@ -39,23 +39,6 @@
 
 #include "std.h"
 
-#if defined(STM32F4)
-/** 25MHz external clock to PLL it to 168MHz */
-const clock_scale_t hse_25mhz_3v3_168mhz = { /* 168MHz */
-  .pllm = 25,
-  .plln = 336,
-  .pllp = 2,
-  .pllq = 7,
-  .hpre = RCC_CFGR_HPRE_DIV_NONE,
-  .ppre1 = RCC_CFGR_PPRE_DIV_4,
-  .ppre2 = RCC_CFGR_PPRE_DIV_2,
-  .flash_config = FLASH_ACR_ICE | FLASH_ACR_DCE |
-                 FLASH_ACR_LATENCY_5WS,
-  .apb1_frequency = 42000000,
-  .apb2_frequency = 84000000,
-};
-#endif
-
 void mcu_arch_init(void) {
 #if LUFTBOOT
 PRINT_CONFIG_MSG("We are running luftboot, the interrupt vector is being relocated.")
@@ -85,7 +68,7 @@ PRINT_CONFIG_MSG("Using 16MHz external clock to PLL it to 168MHz.")
 #elif EXT_CLK == 25000000
 #if defined(STM32F4)
 PRINT_CONFIG_MSG("Using 25MHz external clock to PLL it to 168MHz.")
-  rcc_clock_setup_hse_3v3(&hse_25mhz_3v3_168mhz);
+  rcc_clock_setup_hse_3v3(&hse_25mhz_3v3[CLOCK_3V3_168MHZ]);
 #endif
 #else
 #error EXT_CLK is either set to an unsupported frequency or not defined at all. Please check!

sw/airborne/arch/stm32/mcu_arch.h

@@ -31,7 +31,6 @@
 #define STM32_MCU_ARCH_H
 
 #include "std.h"
-#include <libopencm3/stm32/timer.h>
 
 extern void mcu_arch_init(void);
 
@@ -50,14 +49,6 @@ extern void mcu_arch_init(void);
 #define mcu_int_enable()  {}
 #define mcu_int_disable() {}
 
-/** @todo: these should go into libopencm3 */
-#ifdef TIM9_BASE
-#define TIM9				TIM9_BASE
-#endif
-#ifdef TIM12_BASE
-#define TIM12				TIM12_BASE
-#endif
-
 uint32_t timer_get_frequency(uint32_t timer_peripheral);
 
 #endif /* STM32_MCU_ARCH_H */

sw/airborne/arch/stm32/mcu_periph/i2c_arch.c

@@ -1003,12 +1003,7 @@ void i2c1_hw_init(void) {
   // enable peripheral
   i2c_peripheral_enable(I2C1);
 
-  /*
-   * XXX: there is a function to do that already in libopencm3 but I am not
-   * sure if it is correct, using direct register instead (esden)
-   */
-  //i2c_set_own_7bit_slave_address(I2C1, 0);
-  I2C_OAR1(I2C1) = 0 | 0x4000;
+  i2c_set_own_7bit_slave_address(I2C1, 0);
 
   // enable error interrupts
   i2c_enable_interrupt(I2C1, I2C_CR2_ITERREN);
@@ -1078,12 +1073,7 @@ void i2c2_hw_init(void) {
   // enable peripheral
   i2c_peripheral_enable(I2C2);
 
-  /*
-   * XXX: there is a function to do that already in libopencm3 but I am not
-   * sure if it is correct, using direct register instead (esden)
-   */
-  //i2c_set_own_7bit_slave_address(I2C2, 0);
-  I2C_OAR1(I2C2) = 0 | 0x4000;
+  i2c_set_own_7bit_slave_address(I2C2, 0);
 
   // enable error interrupts
   i2c_enable_interrupt(I2C2, I2C_CR2_ITERREN);
@@ -1153,12 +1143,7 @@ void i2c3_hw_init(void) {
   // enable peripheral
   i2c_peripheral_enable(I2C3);
 
-  /*
-   * XXX: there is a function to do that already in libopencm3 but I am not
-   * sure if it is correct, using direct register instead (esden)
-   */
-  //i2c_set_own_7bit_slave_address(I2C3, 0);
-  I2C_OAR1(I2C3) = 0 | 0x4000;
+  i2c_set_own_7bit_slave_address(I2C3, 0);
 
   // enable error interrupts
   i2c_enable_interrupt(I2C3, I2C_CR2_ITERREN);

sw/airborne/arch/stm32/subsystems/actuators/actuators_shared_arch.c

@@ -23,10 +23,11 @@
  *  STM32 PWM and dualPWM servos shared functions.
  */
 
-#include "subsystems/actuators/actuators_shared_arch.h"
+#include "arch/stm32/subsystems/actuators/actuators_shared_arch.h"
 
+#include <libopencm3/stm32/timer.h>
 // for timer_get_frequency
-#include "mcu_arch.h"
+#include "arch/stm32/mcu_arch.h"
 
 
 /** Set PWM channel configuration