fixed an issue where single block reads on stm32f4 were overflowing on data reads past the 4GB point on SDHC cards, this broke video playback on large AVIs amongst other issues

Author: rikkuness

libs/filesystem/fat_sd/sdio_diskio.c

@@ -115,7 +115,11 @@ BUFFER WE F_READ INTO SHOULD BE 4 BYTES LONGER THAN THE MAX READ REQUEST
     return disk_read_unaligned(drv, buff, sector, count);
 #endif
   if (count<=1)
+    #ifdef STM32F4
+    SD_ReadMultiBlocksFIXED(buff, sector, SECTOR_SIZE, 1);
+    #else
     SD_ReadBlock(Memory_Offset, (uint32_t *)buff, Transfer_Length);
+    #endif
   else
     #ifdef STM32F4
     SD_ReadMultiBlocksFIXED(buff, sector, SECTOR_SIZE, count);