Bug 73607

	Building vtk fails due to C++ ambiguity compile errers
	in IO/vtkBMPReader.cxx and IO/vtkImageReader.cxx.

Fix: 

Patches below from VTK cvs fixes the issue but the port
	did not apply them by simply putting them into vtk/files
	directory.

	http://public.kitware.com/cgi-bin/viewcvs.cgi/IO/vtkBMPReader.cxx?r1=1.44&r2=1.45&makepatch=1&diff_format=u
	http://public.kitware.com/cgi-bin/viewcvs.cgi/IO/vtkImageReader.cxx?r1=1.109&r2=1.110&makepatch=1&diff_format=u
How-To-Repeat: 	#make
	
	(snip)

	Building shared library /usr/ports/math/vtk/work/vtk-build/bin/libvtkGraphics.so...
	/usr/ports/math/vtk/work/vtk-build/IO: building default_target
	building dependencies. cmake.depends...
	Building object file vtkBMPReader.o...
	/usr/ports/math/vtk/work/VTK/IO/vtkBMPReader.cxx: In function `void vtkBMPReaderUpdate2(vtkBMPReader*, vtkImageData*, OT*) [with OT = double]':
	/usr/ports/math/vtk/work/VTK/IO/vtkBMPReader.cxx:545:   instantiated from here
	/usr/ports/math/vtk/work/VTK/IO/vtkBMPReader.cxx:507: error: ISO C++ says that these are ambiguous, even though the worst conversion for the first is better than the worst conversion for the second:
/usr/include/c++/3.4/bits/postypes.h:176: note: candidate 1: std::fpos<_StateT> std::fpos<_StateT>::operator+(std::streamoff) const [with _StateT = mbstate_t]
/usr/ports/math/vtk/work/VTK/IO/vtkBMPReader.cxx:507: note: candidate 2: operator+(std::streamoff, long int) <built-in>

	(snip)