STM32.SDMMC: Fix multiblock write operation
STM32.SDMMC: Fix multiblock write operation

simonjwright/Ada_Drivers_Library,AdaCore/Ada_Drivers_Library,Fabien-Chouteau/Ada_Drivers_Library,AdaCore/Ada_Drivers_Library,Fabien-Chouteau/Ada_Drivers_Library,simonjwright/Ada_Drivers_Library