meta-info: deprecate MetaInfo::TYPE_* constants

The following items are deprecated:

* tlv::ContentType_Default
* MetaInfo::TYPE_DEFAULT
* MetaInfo::TYPE_BLOB
* MetaInfo::TYPE_LINK
* MetaInfo::TYPE_KEY
* MetaInfo::TYPE_NACK

refs #2128

Change-Id: I01f0aa0dd27d32a18a9fff79401b5784d9ddcb10
diff --git a/src/security/certificate.cpp b/src/security/certificate.cpp
index 7173d52..59afa4f 100644
--- a/src/security/certificate.cpp
+++ b/src/security/certificate.cpp
@@ -169,7 +169,7 @@
   idCert.MessageEnd();
 
   setContent(os.buf());
-  setContentType(MetaInfo::TYPE_KEY);
+  setContentType(tlv::ContentType_Key);
 }
 
 void