[bsp][stm32][stm32f769-st-disco]add stm32f7xx_hal_dsi.c when using LTDC/MIPI-DSI

Signed-off-by: WillianChan <chentingwei@rt-thread.com>

bsp/stm32/libraries/STM32F7xx_HAL/SConscript

@@ -99,6 +99,7 @@ if GetDepend(['BSP_USING_LTDC']):
     src += ['STM32F7xx_HAL_Driver/Src/stm32f7xx_hal_ltdc_ex.c']
     src += ['STM32F7xx_HAL_Driver/Src/stm32f7xx_hal_dma2d.c']
     src += ['STM32F7xx_HAL_Driver/Src/stm32f7xx_ll_dma2d.c']
+    src += ['STM32F7xx_HAL_Driver/Src/stm32f7xx_hal_dsi.c']
 
 path = [cwd + '/STM32F7xx_HAL_Driver/Inc',
     cwd + '/CMSIS/Device/ST/STM32F7xx/Include',