Mark EL2 as unused in ATF for arm32 Trusty builds

Bug: 284057071
Test: Build & run Trusty
Change-Id: I5b7e556799671b6fd5298cd29c68640d396726fe
diff --git a/project/qemu-atf-inc.mk b/project/qemu-atf-inc.mk
index 574e7fd..a795153 100644
--- a/project/qemu-atf-inc.mk
+++ b/project/qemu-atf-inc.mk
@@ -52,6 +52,10 @@
 ATF_MAKE_ARGS += DEBUG=$(ATF_DEBUG)
 ATF_MAKE_ARGS += BUILD_BASE=$(ATF_BUILD_BASE)
 ATF_MAKE_ARGS += QEMU_USE_GIC_DRIVER=QEMU_GICV$(GIC_VERSION)
+# On aarch32, we skip EL2, see 27d8e1e75a2f45d7c23
+ifeq (true,$(call TOBOOL,$(KERNEL_32BIT)))
+ATF_MAKE_ARGS += INIT_UNUSED_NS_EL2=1
+endif
 
 ifeq (true,$(call TOBOOL,$(ATF_WITH_TRUSTY_GENERIC_SERVICES)))
 ATF_MAKE_ARGS += TRUSTY_SPD_WITH_GENERIC_SERVICES=1