Revert "pass itcl vars forward"

This reverts commit ec648a3.

We actually don't want to pass these vars forward because they're
potentially unset, and then when passed forward, they're cached and
subsequent find_library() calls skip even checking for it.

Author: brlcad

itk/CMakeLists.txt

@@ -66,9 +66,6 @@ if (ENABLE_ITK)
     -DCMAKE_INSTALL_PREFIX=${CMAKE_BUNDLE_INSTALL_PREFIX}
     -DCMAKE_INSTALL_RPATH=${CMAKE_BUNDLE_INSTALL_PREFIX}/${LIB_DIR}/${RPATH_SUFFIX}
     -DINCLUDE_DIR=${INCLUDE_DIR}
-    -DITCL_LIBRARY=${ITCL_LIBRARY}
-    -DITCL_STUB_LIBRARY=${ITCL_STUB_LIBRARY}
-    -DITCL_INCLUDE_PATH=${ITCL_INCLUDE_PATH}
     -DITCL_ROOT=$<$<BOOL:${ITCL_TARGET}>:${CMAKE_BUNDLE_INSTALL_PREFIX}>
     -DSHARED_DIR=${LIB_DIR}
     -DTCL_ENABLE_TK=ON