Clean up of key block functions

No substantial new code, just making the old code consistent.

Review URL: http://codereview.chromium.org/2729021
diff --git a/utility/vbutil_kernel.c b/utility/vbutil_kernel.c
index 32f844c..a9f7be4 100644
--- a/utility/vbutil_kernel.c
+++ b/utility/vbutil_kernel.c
@@ -326,7 +326,7 @@
 
   /* Verify key block */
   key_block = (VbKeyBlockHeader*)blob;
-  if (0 != VerifyKeyBlock(key_block, blob_size, sign_key)) {
+  if (0 != KeyBlockVerify(key_block, blob_size, sign_key)) {
     error("Error verifying key block.\n");
     return 1;
   }