deprecations.jl: depwarn -> Base.depwarn

Author: skleinbo

src/deprecations.jl

@@ -35,7 +35,7 @@ end
 Zeros(args...) = Zeros()  # was used both Dense(10, 2, initb = Zeros) and Dense(rand(2,10), Zeros())
 
 function Optimise.update!(x::AbstractArray, x̄)
-  depwarn("`Flux.Optimise.update!(x, x̄)` was not used internally and has been removed. Please write `x .-= x̄` instead.", :update!)
+  Base.depwarn("`Flux.Optimise.update!(x, x̄)` was not used internally and has been removed. Please write `x .-= x̄` instead.", :update!)
   x .-= x̄
 end