removing other unnecessary subtraction test

Author: leios

test/atomic_test.jl

@@ -75,11 +75,6 @@ function atomics_testsuite(backend, ArrayT)
 
     @testset "atomic subtraction tests" begin
         types = [Int32, Int64, UInt32, UInt64, Float32]
-        if ArrayT == CuArray
-            CUDA.capability(CUDA.device()) >= v"6.0" && push!(types, Float64)
-        else
-            push!(types, Float64)
-        end
 
         for T in types
             A = ArrayT{T}([2048,2048])