FIT: Fix handling of images without ramdisks

boot_get_ramdisk() should not treat the case when a FIT image does
not contain a ramdisk as an error.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Acked-by: Michal Simek <monstr@monstr.eu>
diff --git a/common/image.c b/common/image.c
index 535c302..c3545a7 100644
--- a/common/image.c
+++ b/common/image.c
@@ -833,7 +833,7 @@
 			rd_noffset = fit_conf_get_ramdisk_node (fit_hdr, cfg_noffset);
 			if (rd_noffset < 0) {
 				debug ("*  ramdisk: no ramdisk in config\n");
-				return 1;
+				return 0;
 			}
 		}
 #endif