COMP: Fix undeclared identifier error

[jhlegarreta]

Fix undeclared identifier error.

Fixes:

In file included from
/Users/builder/externalModules/Filtering/FFT/test/itkComplexToComplex1DFFTImageFilterTest.cxx:27:
/Users/builder/externalModules/Filtering/FFT/include/itkComplexToComplex1DFFTImageFilter.h:84:48:
error: use of undeclared identifier 'ImageDimension'
  itkSetClampMacro(Direction, unsigned int, 0, ImageDimension - 1);
                                               ^

and

In file included from
/Users/builder/externalModules/Filtering/FFT/test/itkFFT1DImageFilterTest.cxx:25:
/Users/builder/externalModules/Filtering/FFT/include/itkForward1DFFTImageFilter.h:67:48:
error: use of undeclared identifier 'ImageDimension'
  itkSetClampMacro(Direction, unsigned int, 0, ImageDimension - 1);
                                               ^

and

In file included from
/Users/builder/externalModules/Filtering/FFT/test/itkInverse1DFFTImageFilterTest.cxx:26:
/Users/builder/externalModules/Filtering/FFT/include/itkInverse1DFFTImageFilter.h:68:48:
error: use of undeclared identifier 'ImageDimension'
  itkSetClampMacro(Direction, unsigned int, 0, ImageDimension - 1);
                                               ^

reported for example at:
https://open.cdash.org/viewBuildError.php?buildid=7505348

PR Checklist

• No API changes were made (or the changes have been approved)
• No major design changes were made (or the changes have been approved)

[tbirdso]

Good catch. LGTM provided that CI passes.

1D FFT files were originally added to ITKUltrasound a few years ago and it looks like there are some "growing pains" from adding them to ITK proper. Thanks again for resolving issues where they arise.

[thewtex]

@jhlegarreta thank you!!