scons: Move CPPPATH systemc_home to "src/systemc" folder (#617)

Files under src/systemc require the include path of systemc_home

Change-Id: Ibcbac2762259a0b997ac444b2c63a218c27af9ee

src/arch/arm/fastmodel/SConscript

@@ -50,10 +50,6 @@ import os.path
 if env['CONF']['USE_ARM_FASTMODEL']:
     env.TagImplies('arm fastmodel', 'arm isa')
 
-
-systemc_home = Dir('#/src/systemc/ext/systemc_home')
-env['ENV']['SYSTEMC_HOME'] = systemc_home.abspath
-
 def extract_var(name):
     val = env['CONF'].get(name, None)
     if val is None:
@@ -114,8 +110,6 @@ cpppaths = (
     pvlib_home.Dir('include/fmruntime/eslapi'),
     pvlib_home.Dir('Iris/include'),
 
-    systemc_home.Dir('include'),
-
     maxcore_home.Dir('AMBA-PV/include'),
 )
 env.Append(CPPPATH=cpppaths)

src/systemc/SConscript

@@ -30,6 +30,9 @@ if not env['CONF']['USE_SYSTEMC']:
 
 env.UseSystemcCheck(warn=True)
 
-env.Append(CPPPATH=Dir('ext'))
+systemc_home = Dir('#/src/systemc/ext/systemc_home')
+env['ENV']['SYSTEMC_HOME'] = systemc_home.abspath
+
+env.Append(CPPPATH=[systemc_home.Dir('include'),Dir('ext')])
 
 SimObject('Tlm.py', sim_objects=[])