CMakeLists.txt: set ITKPythonPackage_WHEEL_NAME earlier

This fixes building the monolithic "itk" Python package because we
define the variable before the checks like:

  if(NOT ITKPythonPackage_WHEEL_NAME STREQUAL "itk")

Author: thewtex

CMakeLists.txt

@@ -9,6 +9,11 @@ if(NOT DEFINED ITKPythonPackage_SUPERBUILD)
   set(ITKPythonPackage_SUPERBUILD 1)
 endif()
 
+if(NOT DEFINED ITKPythonPackage_WHEEL_NAME)
+  set(ITKPythonPackage_WHEEL_NAME "itk")
+endif()
+message(STATUS "SuperBuild - ITKPythonPackage_WHEEL_NAME:${ITKPythonPackage_WHEEL_NAME}")
+
 if(ITKPythonPackage_SUPERBUILD)
 
   #-----------------------------------------------------------------------------
@@ -225,11 +230,6 @@ if(ITKPythonPackage_SUPERBUILD)
   message(STATUS "SuperBuild -")
   message(STATUS "SuperBuild - ${PROJECT_NAME} => Requires ITK")
 
-  if(NOT DEFINED ITKPythonPackage_WHEEL_NAME)
-    set(ITKPythonPackage_WHEEL_NAME "itk")
-  endif()
-  message(STATUS "SuperBuild -   ITKPythonPackage_WHEEL_NAME:${ITKPythonPackage_WHEEL_NAME}")
-
   ExternalProject_add(${PROJECT_NAME}
     SOURCE_DIR ${CMAKE_SOURCE_DIR}
     BINARY_DIR ${CMAKE_BINARY_DIR}/${PROJECT_NAME}-build