cmake: create script only if SIMULATION is enabled

The simulation scripts are useless if the target is a real board and
not a QEMU simulation. Thus they will only be created if SIMULATION
is explicitly ON (-DSIMULATION=TRUE).
SIMULATION is disabled by default

Signed-off-by: ichdream <chensheng0802@outlook.com>

Author: ichdream

CMakeLists.txt

@@ -30,12 +30,13 @@ elfloader_import_project()
 
 add_subdirectory(apps/sel4test-driver)
 
-include(simulation)
-if(KernelSel4ArchX86_64)
-    SetSimulationScriptProperty(MEM_SIZE "3G")
+if(SIMULATION)
+    include(simulation)
+    if(KernelSel4ArchX86_64)
+        SetSimulationScriptProperty(MEM_SIZE "3G")
+    endif()
+    if(KernelPlatformQEMUArmVirt)
+        SetSimulationScriptProperty(MEM_SIZE "2G")
+    endif()
+    GenerateSimulateScript()
 endif()
-if(KernelPlatformQEMUArmVirt)
-    SetSimulationScriptProperty(MEM_SIZE "2G")
-endif()
-
-GenerateSimulateScript()