SPL: fix printing of image name

The maximum length of the name of the image is
obviously not sizeof(), which is just the
length of a pointer, but IH_NMLEN.

fixes: 62cf11c0921a90c6bd62344f4bc069668e6c698c
("SPL: Limit image name print length")

Signed-off-by: André Draszik <adraszik@tycoint.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/common/spl/spl.c b/common/spl/spl.c
index aaddddd..d232f67 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -154,7 +154,7 @@
 		spl_image->os = image_get_os(header);
 		spl_image->name = image_get_name(header);
 		debug("spl: payload image: %.*s load addr: 0x%lx size: %d\n",
-			(int)sizeof(spl_image->name), spl_image->name,
+			IH_NMLEN, spl_image->name,
 			spl_image->load_addr, spl_image->size);
 #else
 		/* LEGACY image not supported */