boot: Update pxe bootmeth to record images

Record images loaded by this bootmeth.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/boot/bootmeth_pxe.c b/boot/bootmeth_pxe.c
index b287307..b91e61b 100644
--- a/boot/bootmeth_pxe.c
+++ b/boot/bootmeth_pxe.c
@@ -135,6 +135,9 @@
 		return log_msg_ret("spc", -ENOSPC);
 	*sizep = size;
 
+	if (!bootflow_img_add(bflow, file_path, type, addr, size))
+		return log_msg_ret("pxi", -ENOMEM);
+
 	return 0;
 }