feat(rme): disable Watchdog for Arm platforms if FEAT_RME enabled

In the typical TF-A boot flow, the Trusted Watchdog is started
at the beginning of BL1 and then stopped in BL1 after returning
from BL2. However, in the RME boot flow there is no return path
from BL2 to BL1. Therefore, disable the Watchdog if ENABLE_RME is set.

Signed-off-by: Zelalem Aweke <zelalem.aweke@arm.com>
Change-Id: Id88fbfab8e8440642414bed48c50e3fcb23f3621
diff --git a/plat/arm/common/arm_common.mk b/plat/arm/common/arm_common.mk
index ae9afb7..d14d101 100644
--- a/plat/arm/common/arm_common.mk
+++ b/plat/arm/common/arm_common.mk
@@ -52,9 +52,10 @@
 $(eval $(call add_define,ARM_RECOM_STATE_ID_ENC))
 
 # Process ARM_DISABLE_TRUSTED_WDOG flag
-# By default, Trusted Watchdog is always enabled unless SPIN_ON_BL1_EXIT is set
+# By default, Trusted Watchdog is always enabled unless
+# SPIN_ON_BL1_EXIT or ENABLE_RME is set
 ARM_DISABLE_TRUSTED_WDOG	:=	0
-ifeq (${SPIN_ON_BL1_EXIT}, 1)
+ifneq ($(filter 1,${SPIN_ON_BL1_EXIT} ${ENABLE_RME}),)
 ARM_DISABLE_TRUSTED_WDOG	:=	1
 endif
 $(eval $(call assert_boolean,ARM_DISABLE_TRUSTED_WDOG))