tools: imx8mimage: Fix handle leak

The handle "fd" was created in imx8mimage.c:178 by calling
 the "fopen" function and is lost in imx8mimage.c:210.
 Should close the 'fd' file descriptor before exiting
 the parse_cfg_file(char *name) function.

Fixes: 6609c2663c9c ("tools: add i.MX8M image support")
Signed-off-by: Mikhail Ilin <ilin.mikhail.ol@gmail.com>
diff --git a/tools/imx8mimage.c b/tools/imx8mimage.c
index 35d0a92..3ca79d8 100644
--- a/tools/imx8mimage.c
+++ b/tools/imx8mimage.c
@@ -207,6 +207,7 @@
 		}
 	}
 
+	fclose(fd);
 	return 0;
 }