AthenaPython: cmake cleanup

- remove atlas_depend_on_subdirs
- minimize ROOT component dependencies
- update link dependencies

Control/AthenaPython/CMakeLists.txt

-################################################################################
-# Package: AthenaPython
-################################################################################
+# Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 
 # Declare the package name:
 atlas_subdir( AthenaPython )
 
-# Declare the package's dependencies:
-atlas_depends_on_subdirs( PUBLIC
-                          Control/AthenaBaseComps
-                          Control/AthenaKernel
-                          Control/StoreGate
-                          GaudiKernel
-                          PRIVATE
-                          Control/RootUtils
-                          Control/DataModelRoot )
-
 # External dependencies:
 find_package( Python COMPONENTS Development )
-find_package( ROOT COMPONENTS Core Tree MathCore Hist RIO pthread PyROOT )
+find_package( ROOT COMPONENTS Core PyROOT )
 
 # Component(s) in the package:
 atlas_add_library( AthenaPython
@@ -25,18 +13,16 @@ atlas_add_library( AthenaPython
                    PUBLIC_HEADERS AthenaPython
                    PRIVATE_INCLUDE_DIRS ${ROOT_INCLUDE_DIRS} ${Python_INCLUDE_DIRS}
                    LINK_LIBRARIES AthenaBaseComps AthenaKernel GaudiKernel
-                   PRIVATE_LINK_LIBRARIES ${ROOT_LIBRARIES} ${Python_LIBRARIES} CxxUtils DataModelRoot )
+                   PRIVATE_LINK_LIBRARIES ${ROOT_LIBRARIES} ${Python_LIBRARIES} CxxUtils DataModelRoot RootUtils )
 
 atlas_add_component( AthenaPythonComps
                      src/components/*.cxx
-                     INCLUDE_DIRS ${ROOT_INCLUDE_DIRS} ${Python_INCLUDE_DIRS}
                      LINK_LIBRARIES AthenaPython )
 
 atlas_add_dictionary( AthenaPythonDict
                       AthenaPython/AthenaPythonDict.h
                       AthenaPython/selection.xml
-                      INCLUDE_DIRS ${ROOT_INCLUDE_DIRS} ${Python_INCLUDE_DIRS}
-                      LINK_LIBRARIES ${ROOT_LIBRARIES} ${Python_LIBRARIES} AthenaBaseComps AthenaKernel GaudiKernel CxxUtils DataModelRoot AthenaPython )
+                      LINK_LIBRARIES AthenaPython )
 
 # Install files from the package:
 atlas_install_python_modules( python/*.py python/tests