[SYCL][NVPTX][AMDGCN] Move std::complex to headers (#19572)
This follows 4f0afd5e47ae2c6c8238c998a11a5ee391c8455f and moves
implementation of std::complex operations from libdevice to a header.
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Co-authored-by: Marcos Maronas <marcos.maronas@intel.com>
