configs: Remove security option

If willing to run a secure software stack, we recommend to use
the baremetal.py platform
See [1] on how to run gem5 with TF-A

[1]: https://community.arm.com/developer/research/b/articles/\
    posts/running-trusted-firmware-a-on-gem5

Change-Id: I69f6d672b24cb588c522c6a468e3b19332c9367b
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/51008
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>

configs/common/FSConfig.py

@@ -173,7 +173,7 @@ def makeSparcSystem(mem_mode, mdesc=None, cmdline=None):
 
 def makeArmSystem(mem_mode, machine_type, num_cpus=1, mdesc=None,
                   dtb_filename=None, bare_metal=False, cmdline=None,
-                  external_memory="", ruby=False, security=False,
+                  external_memory="", ruby=False,
                   vio_9p=None, bootloader=None):
     assert machine_type
 
@@ -236,8 +236,6 @@ def makeArmSystem(mem_mode, machine_type, num_cpus=1, mdesc=None,
               " the amount of DRAM you've selected. Please try" \
               " another platform")
 
-    self.have_security = security
-
     if bare_metal:
         # EOT character on UART will end the simulation
         self.realview.uart[0].end_on_eot = True

configs/common/Options.py

@@ -490,9 +490,6 @@ def addFSOptions(parser):
             "--dtb-filename", action="store", type=str,
             help="Specifies device tree blob file to use with device-tree-"
             "enabled kernels")
-        parser.add_argument(
-            "--enable-security-extensions", action="store_true",
-            help="Turn on the ARM Security Extensions")
         parser.add_argument(
             "--enable-context-switch-stats-dump", action="store_true",
             help="Enable stats dump at context "

configs/example/fs.py

@@ -97,7 +97,6 @@ def build_test_system(np):
             cmdline=cmdline,
             external_memory=args.external_memory_system,
             ruby=args.ruby,
-            security=args.enable_security_extensions,
             vio_9p=args.vio_9p,
             bootloader=args.bootloader,
         )