[bzimage] Kill off the initrd image type

We can just treat all non-kernel images as initrds, which matches our
behaviour for multiboot kernels.  This allows us to eliminate initrd as
an image type, and treat the "initrd" command as just another synonym for
"imgfetch".

src/arch/i386/image/bzimage.c

 #include <gpxe/image.h>
 #include <gpxe/segment.h>
 #include <gpxe/init.h>
-#include <gpxe/initrd.h>
 #include <gpxe/cpio.h>
 #include <gpxe/features.h>
 
 	struct cpio_header cpio;
         size_t offset = 0;
 
-	/* Ignore images which aren't initrds */
-	if ( initrd->type != &initrd_image_type )
+	/* Do not include kernel image itself as an initrd */
+	if ( initrd == image )
 		return 0;
 
 	/* Create cpio header before non-prebuilt images */

src/hci/commands/image_cmd.c

 #include <getopt.h>
 #include <gpxe/image.h>
 #include <gpxe/command.h>
-#include <gpxe/initrd.h>
 #include <usr/imgmgmt.h>
 
 /** @file
 	return 0;
 }
 
-/**
- * The "initrd" command
- *
- * @v argc		Argument count
- * @v argv		Argument list
- * @ret rc		Exit code
- */
-static int initrd_exec ( int argc, char **argv ) {
-	int rc;
-
-	if ( ( rc = imgfetch_core_exec ( &initrd_image_type, IMG_FETCH,
-					 argc, argv ) ) != 0 )
-		return rc;
-
-	return 0;
-}
-
 /**
  * "imgload" command syntax message
  *
 		.exec = imgfetch_exec, /* synonym for "imgfetch" */
 	},
 	{
-		.name = "kernel",
-		.exec = kernel_exec,
+		.name = "initrd",
+		.exec = imgfetch_exec, /* synonym for "imgfetch" */
 	},
 	{
-		.name = "initrd",
-		.exec = initrd_exec,
+		.name = "kernel",
+		.exec = kernel_exec,
 	},
 	{
 		.name = "imgload",

src/image/initrd.c

-/*
- * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-/**
- * @file
- *
- * Linux initrd image format
- *
- * This file does nothing except provide a way to mark images as being
- * initrds.  The actual processing is done in the Linux kernel image
- * code; this file exists so that we can include the "initrd" command
- * without necessarily dragging in the Linux image format.
- *
- */
-
-#include <gpxe/image.h>
-#include <gpxe/initrd.h>
-
-/** Linux initrd image type */
-struct image_type initrd_image_type __image_type ( PROBE_NORMAL ) = {
-	.name = "initrd",
-};

src/include/gpxe/initrd.h

-#ifndef _GPXE_INITRD_H
-#define _GPXE_INITRD_H
-
-/**
- * @file
- *
- * Linux initrd image format
- *
- */
-
-#include <gpxe/image.h>
-extern struct image_type initrd_image_type __image_type ( PROBE_NORMAL );
-
-#endif /* _GPXE_INITRD_H */