stm32/sdcard: Add switch break to ensure only correct SD/MMC IRQ is run.

ports/stm32/sdcard.c

@@ -370,10 +370,12 @@ STATIC void sdmmc_irq_handler(void) {
         #if MICROPY_HW_ENABLE_SDCARD
         case PYB_SDMMC_FLAG_ACTIVE | PYB_SDMMC_FLAG_SD:
             HAL_SD_IRQHandler(&sdmmc_handle.sd);
+            break;
         #endif
         #if MICROPY_HW_ENABLE_MMCARD
         case PYB_SDMMC_FLAG_ACTIVE | PYB_SDMMC_FLAG_MMC:
             HAL_MMC_IRQHandler(&sdmmc_handle.mmc);
+            break;
         #endif
     }
 }