Validate input to C2CPlan::c2c and R2RPlan::r2r
Validate input to C2CPlan::c2c and R2RPlan::r2r

The underlying C function requires that the arrays passed into it have the same length and alignment as was used to create the plan.
Adding this check prevents out-of-bounds reads and possibly writes.

The same check is already in place for C2R and R2C plans.

Fixes: https://github.com/rust-math/fftw/commit/3e84ddd4f7deb583ff4ca8b47ee266576021fac5
Fixes: https://github.com/rust-math/fftw/commit/862fead9b7e815c7914acccf50106702a89beaff

termoshtt/rust-fftw3