[stm32h750-artpi][Kconfig] add SPI3 (#6382)

* [add] board/Kconfig 完善SPI3部分

* [add] 提交代码注释
Co-authored-by: Man, Jianting (Meco) <920369182@qq.com>

bsp/stm32/stm32h750-artpi/board/Kconfig

@@ -185,6 +185,9 @@ menu "On-chip Peripheral Drivers"
             config BSP_USING_SPI2
                 bool "Enable SPI2"
                 default n
+            config BSP_USING_SPI3
+                bool "Enable SPI3"
+                default n
             config BSP_USING_SPI4
                 bool "Enable SPI4"
                 default n