Added the embedded pxelinux payload patch from hpa.

src/image/embed.S

@@ -0,0 +1,7 @@
+	.section ".data", "aw"
+	.balign 4
+	.globl _embedded_image_start
+_embedded_image_start:
+	.incbin EMBEDIMG
+	.globl _embedded_image_end
+_embedded_image_end:

src/image/embedded.c

@@ -0,0 +1,49 @@
+/** @file
+ *
+ * Take a possible embedded image and put it in a struct image
+ * data structure.
+ */
+
+#include <stdio.h>
+#include <gpxe/image.h>
+#include <gpxe/malloc.h>
+#include <gpxe/uaccess.h>
+#include <gpxe/umalloc.h>
+#include <gpxe/embedded.h>
+
+extern char _embedded_image_start[], _embedded_image_end[];
+
+struct image *embedded_image(void)
+{
+	static int reclaimed = 0;
+	struct image *image;
+	size_t eisize = _embedded_image_end - _embedded_image_start;
+
+	if ( !eisize )
+		return NULL;	/* No embedded image */
+
+	if ( reclaimed )
+		return NULL;	/* Already reclaimed */
+
+	printf("Embedded image: %d bytes at %p\n",
+	       eisize, _embedded_image_start);
+
+	image = alloc_image();
+	if (!image)
+		return NULL;
+
+	image->len     = eisize;
+	image->data    = umalloc(eisize);
+	if (image->data == UNULL) {
+		image_put(image);
+		return image = NULL;
+	}
+	copy_to_user(image->data, 0, _embedded_image_start, eisize);
+
+	/* Reclaim embedded image memory */
+	reclaimed = 1;
+	mpopulate(_embedded_image_start, eisize);
+
+	return image;
+}
+