Adds missing declarations in periph.h for stm32f767xx

Author: k0d

ports/stm/peripherals/stm32f7/stm32f767xx/periph.h

@@ -50,6 +50,8 @@ const mcu_periph_obj_t mcu_uart_rx_list[25];
 //Timers
 #define TIM_BANK_ARRAY_LEN 14
 #define TIM_PIN_ARRAY_LEN 55
-TIM_TypeDef * mcu_tim_banks[TIM_BANK_ARRAY_LEN];
+extern TIM_TypeDef * mcu_tim_banks[TIM_BANK_ARRAY_LEN];
+
+const mcu_tim_pin_obj_t mcu_tim_pin_list[TIM_PIN_ARRAY_LEN];
 
 #endif // MICROPY_INCLUDED_STM32_PERIPHERALS_STM32F767XX_PERIPH_H