STM32C051xx missing GPIO_AF0_USART2 definition

[fpistm]

According to datasheet DS14721 Rev 2, PD3 can have USART2_CTS/USART2_NSS with AF0 but HAL GPIO does not define it for this part number:

stm32c0xx-hal-driver/Inc/stm32c0xx_hal_gpio_ex.h

Lines 64 to 66 in c283b14

	#if defined(STM32C031xx) || defined(STM32C071xx) || defined(STM32C091xx) || defined(STM32C092xx)
	#define GPIO_AF0_USART2 ((uint8_t)0x00) /*!< USART2 Alternate Function mapping */
	#endif /* STM32C031xx | STM32C071xx | STM32C091xx | STM32C092xx*/

Proposed patch:

- #if defined(STM32C031xx) || defined(STM32C071xx) || defined(STM32C091xx)  || defined(STM32C092xx) 
+ #if defined(STM32C031xx) || defined(STM32C051xx) || defined(STM32C071xx) || defined(STM32C091xx)  || defined(STM32C092xx) 
 #define GPIO_AF0_USART2        ((uint8_t)0x00)  /*!< USART2 Alternate Function mapping */ 
- #endif /* STM32C031xx | STM32C071xx | STM32C091xx | STM32C092xx*/ 
+ #endif /* STM32C031xx | STM32C051xx | STM32C071xx | STM32C091xx | STM32C092xx*/ 

Issue reported by @nessotrin in a PR:
stm32duino/Arduino_Core_STM32#2791

[KRASTM]

ST Internal Reference: 219980

[KRASTM]

Fixed in Commit: 18bb669