[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/board/mcc200/auto_update.c b/board/mcc200/auto_update.c
index fcae35a..5580c11 100644
--- a/board/mcc200/auto_update.c
+++ b/board/mcc200/auto_update.c
@@ -144,7 +144,7 @@
 
 	hdr = (image_header_t *)LOAD_ADDR;
 #if defined(CONFIG_FIT)
-	if (gen_image_get_format ((void *)hdr) != IMAGE_FORMAT_LEGACY) {
+	if (genimg_get_format ((void *)hdr) != IMAGE_FORMAT_LEGACY) {
 		puts ("Non legacy image format not supported\n");
 		return -1;
 	}
@@ -169,7 +169,7 @@
 
 	hdr = (image_header_t *)LOAD_ADDR;
 #if defined(CONFIG_FIT)
-	if (gen_image_get_format ((void *)hdr) != IMAGE_FORMAT_LEGACY) {
+	if (genimg_get_format ((void *)hdr) != IMAGE_FORMAT_LEGACY) {
 		puts ("Non legacy image format not supported\n");
 		return -1;
 	}
@@ -247,7 +247,7 @@
 
 	hdr = (image_header_t *)LOAD_ADDR;
 #if defined(CONFIG_FIT)
-	if (gen_image_get_format ((void *)hdr) != IMAGE_FORMAT_LEGACY) {
+	if (genimg_get_format ((void *)hdr) != IMAGE_FORMAT_LEGACY) {
 		puts ("Non legacy image format not supported\n");
 		return -1;
 	}