docs: change FVP argument in RME configuration

In RME documentation use "bp.secure_memory=0" to disable TZC,
and avoid conflicts with SPM in 4-world configuration.

Signed-off-by: J-Alves <joao.alves@arm.com>
Change-Id: I532bca8ab3bd3e6d4f18b5aa7e848c533e016f39
diff --git a/docs/components/realm-management-extension.rst b/docs/components/realm-management-extension.rst
index f228e6b..39186b4 100644
--- a/docs/components/realm-management-extension.rst
+++ b/docs/components/realm-management-extension.rst
@@ -237,7 +237,7 @@
  -C bp.ve_sysregs.exit_on_shutdown=1                            \
  -C cache_state_modelled=1                                      \
  -C bp.dram_size=4                                              \
- -C bp.secure_memory=1                                          \
+ -C bp.secure_memory=0                                          \
  -C pci.pci_smmuv3.mmu.SMMU_ROOT_IDR0=3                         \
  -C pci.pci_smmuv3.mmu.SMMU_ROOT_IIDR=0x43B                     \
  -C pci.pci_smmuv3.mmu.root_register_page_offset=0x20000        \