STYLE: Remove variable that is always set to OFF
STYLE: Remove variable that is always set to OFF

The local variable 'default' was always set to OFF for
at least the last 6 years.  Simply remove unmutable
variable.

thewtex/ITK,richardbeare/ITK,BRAINSia/ITK,hjmjohnson/ITK,InsightSoftwareConsortium/ITK,BRAINSia/ITK,richardbeare/ITK,Kitware/ITK,BRAINSia/ITK,InsightSoftwareConsortium/ITK,thewtex/ITK,Kitware/ITK,BRAINSia/ITK,richardbeare/ITK,hjmjohnson/ITK,richardbeare/ITK,BRAINSia/ITK,thewtex/ITK,InsightSoftwareConsortium/ITK,InsightSoftwareConsortium/ITK,thewtex/ITK,BRAINSia/ITK,Kitware/ITK,Kitware/ITK,hjmjohnson/ITK,thewtex/ITK,Kitware/ITK,richardbeare/ITK,InsightSoftwareConsortium/ITK,hjmjohnson/ITK,Kitware/ITK,richardbeare/ITK,thewtex/ITK,InsightSoftwareConsortium/ITK,BRAINSia/ITK,hjmjohnson/ITK,hjmjohnson/ITK,richardbeare/ITK,hjmjohnson/ITK,thewtex/ITK,Kitware/ITK,InsightSoftwareConsortium/ITK