[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/mpl/common/common_util.c b/board/mpl/common/common_util.c
index fffd25c..785d204 100644
--- a/board/mpl/common/common_util.c
+++ b/board/mpl/common/common_util.c
@@ -74,7 +74,7 @@
 	info = &flash_info[0];
 
 #if defined(CONFIG_PIP405) || defined(CONFIG_MIP405) || defined(CONFIG_PATI)
-	if (image_to_cpu (magic[0]) != IH_MAGIC) {
+	if (uimage_to_cpu (magic[0]) != IH_MAGIC) {
 		puts("Bad Magic number\n");
 		return -1;
 	}
@@ -182,7 +182,7 @@
 	int rc;
 
 #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;
 	}