Log Message:
Update to 3.2.2. Set LICENSE to gnu-gpl-v2.

FFTW 3.2.2

* Improve performance of some copy operations of complex arrays on
  x86 machines.

* Add configure flag to disable alloca(), which is broken in mingw64.

* Planning in FFTW_ESTIMATE mode for r2r transforms became slower
  between fftw-3.1.3 and 3.2.  This regression has now been fixed.