Remove unused ldexp code

Author: kshyatt

base/math.jl

@@ -1152,7 +1152,6 @@ Return positive part of the high word of `x` as a `UInt32`.
 # More special functions
 include("special/cbrt.jl")
 include("special/exp.jl")
-include("special/ldexp_exp.jl")
 include("special/hyperbolic.jl")
 include("special/trig.jl")
 include("special/rem_pio2.jl")