tools: imx8image: Fix handle leak

The handle "fd" was created in imx8image.c:249 by calling the "fopen"
 function and is lost in imx8image.c:282.
 Should close the 'fd' file descriptor before exiting the
 parse_cfg_file(image_t *param_stack, char *name) function.

Fixes: a2b96ece5b ("tools: add i.MX8/8X image support")
Signed-off-by: Mikhail Ilin <ilin.mikhail.ol@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

tools/imx8image.c

@@ -279,6 +279,7 @@ static uint32_t parse_cfg_file(image_t *param_stack, char *name)
 		}
 	}
 
+	fclose(fd);
 	return 0;
 }