desktop: fixed malloc cast

libraries/Desktop/support/DataFlash.cpp

@@ -30,7 +30,7 @@ void DataFlash_Class::Init(void)
 		flash_fd = open("dataflash.bin", O_RDWR, 0777);
 		if (flash_fd == -1) {
 			uint8_t *fill;
-			fill = malloc(DF_PAGE_SIZE*DF_NUM_PAGES);
+			fill = (uint8_t *)malloc(DF_PAGE_SIZE*DF_NUM_PAGES);
 			flash_fd = open("dataflash.bin", O_RDWR | O_CREAT, 0777);
 			memset(fill, 0xFF, DF_PAGE_SIZE*DF_NUM_PAGES);
 			write(flash_fd, fill, DF_PAGE_SIZE*DF_NUM_PAGES);