Revert "realcomplex_even: remove dead 2D/3D pre/post processing code"
Revert "realcomplex_even: remove dead 2D/3D pre/post processing code"

This reverts commit 03512f10fea092a3227b3eb3f55a1bd0fb98ad3f, as we still
want the ability to run unoptimized plans.
ROCmSoftwarePlatform/rocFFT,ROCmSoftwarePlatform/rocFFT,ROCmSoftwarePlatform/rocFFT,ROCmSoftwarePlatform/rocFFT