Use CUDA APIs for unoptimized copies.

[maleadt]

Fixes #1263

[codecov]

Codecov Report

Merging #1265 (00b6476) into master (4f6dfbd) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #1265   +/-   ##
=======================================
  Coverage   78.68%   78.68%           
=======================================
  Files         119      119           
  Lines        8626     8626           
=======================================
  Hits         6787     6787           
  Misses       1839     1839           

Impacted Files	Coverage Δ
src/array.jl	91.15% <100.00%> (ø)

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