Correct typos

Author: simsurace

src/MetaGraphs.jl

@@ -583,13 +583,13 @@ include("persistence.jl")
 include("overrides.jl")
 
 function __init__()
-    # Register error hint for the `loadmg`, `savemg`, and `savedot` functions
+    # Register error hint for the `loadmg` and `savemg`
     if isdefined(Base.Experimental, :register_error_hint)
         Base.Experimental.register_error_hint(MethodError) do io, exc, _, _
-            if exc.f === loadsg
+            if exc.f === loadmg
                 print(io, "\n\nIn order to load meta graphs from binary files, you need \
                 to load the JLD2.jl package.")
-            elseif exc.f === savesg
+            elseif exc.f === savemg
                 print(io,"\n\nIn order to save meta graphs to binary files, you need to \
                 load the JLD2.jl package.")
             end