test-suite with Octave: cannot allocate pointer

[KrisThielemans]

The following 2 tests fail with Octave after #96 (but are fine with MATLAB)

• 'multi_import.multicpptest

  multi_import_runme at line 6 column 3
  ERROR: multi_import_aMEX: Cannot allocate pointer

• template_typedef_import.multicpptest

  template_typedef_import_runme at line 6 column 3
  ERROR: template_typedef_cplx2MEX: Cannot allocate pointer

Originally posted by @KrisThielemans in https://github.com/jaeandersson/swig/issues/96#issuecomment-998434304