Update IETF-RFC.md

Co-authored-by: Giuseppe Lo Presti <[email protected]>

Author: mickenordin

IETF-RFC.md

@@ -87,7 +87,7 @@ they appear in all capitals, as shown here.
 
 ## Functions
 
-Open Cloud Mesh defines distinct functions, it is not neccessary for an
+Open Cloud Mesh defines distinct functions.  It is not necessary for an
 implementation to provide all of them.  In fact, it may be useful to
 have separate implementations for different functions.