fix fillmap show

Author: dkarrasch

src/show.jl

@@ -39,8 +39,8 @@ end
 function _show(io::IO, A::ScaledMap{T}, i) where {T}
     " with scale: $(A.λ) of\n" * map_show(io, A.lmap, i+2)
 end
-function _show(io::IO, A::FillMap{T}) where {T}
-    println(io, " with fill value: $(A.λ)")
+function _show(io::IO, A::FillMap{T}, _) where {T}
+    " with fill value: $(A.λ)"
 end
 
 # helper functions