boot: Support booti format in bootm

At present the booti format is handled separately, in its own command.
Provide a way to boot uncompressed booti images within the bootm code,
so that eventually we can boot these images without CONFIG_CMDLINE

Update bootm_init() to attach the images for all formats which use them.

Add some debugging while we are here.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/image.h b/include/image.h
index f8f2c88..5b9bd6a 100644
--- a/include/image.h
+++ b/include/image.h
@@ -244,7 +244,7 @@
  * New IDs *MUST* be appended at the end of the list and *NEVER*
  * inserted for backward compatibility.
  */
-enum {
+enum image_comp_t {
 	IH_COMP_NONE		= 0,	/*  No	 Compression Used	*/
 	IH_COMP_GZIP,			/* gzip	 Compression Used	*/
 	IH_COMP_BZIP2,			/* bzip2 Compression Used	*/