[new uImage] Update naming convention for bootm/uImage related code

This patch introduces the following prefix convention for the
image format handling and bootm related code:

genimg_		- dual format shared code
image_		- legacy uImage format specific code
fit_		- new uImage format specific code
boot_		- booting process related code

Related routines are renamed and a few pieces of code are moved around and
re-grouped.

Signed-off-by: Marian Balakowicz <m8@semihalf.com>
diff --git a/common/cmd_ximg.c b/common/cmd_ximg.c
index 4dadc37..360b05e 100644
--- a/common/cmd_ximg.c
+++ b/common/cmd_ximg.c
@@ -57,7 +57,7 @@
 	}
 
 
-	switch (gen_image_get_format ((void *)addr)) {
+	switch (genimg_get_format ((void *)addr)) {
 	case IMAGE_FORMAT_LEGACY:
 
 		printf("## Copying from legacy image at %08lx ...\n", addr);
@@ -104,7 +104,7 @@
 			data += 4;
 			if (argc > 2 && part > i) {
 				u_long tail;
-				len = image_to_cpu (len_ptr[i]);
+				len = uimage_to_cpu (len_ptr[i]);
 				tail = len % 4;
 				data += len;
 				if (tail) {
@@ -116,7 +116,7 @@
 			printf("Bad Image Part\n");
 			return 1;
 		}
-		len = image_to_cpu (len_ptr[part]);
+		len = uimage_to_cpu (len_ptr[part]);
 #if defined(CONFIG_FIT)
 	case IMAGE_FORMAT_FIT:
 		fit_unsupported ("imxtract");