feat: add support for SP805 Trusted watchdog module helper APIs

We leverage this module to generate secure interrupts which we
plan to use for exercising secure interrupt handling support in
SPM(Hafnium) in co-ordination with Cactus SP

Correspondingly, a device region node is added to the Cactus primary
SP manifest which captures the base address as well as other related
properties such as interrupts.

Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
Change-Id: I410fdf926a23bd438e9899320f43a77e3697bc91
diff --git a/drivers/arm/sp805/sp805.c b/drivers/arm/sp805/sp805.c
index 6893ebb..85da43a 100644
--- a/drivers/arm/sp805/sp805.c
+++ b/drivers/arm/sp805/sp805.c
@@ -166,3 +166,18 @@
 {
 	sp805_wdog_refresh_(SP805_WDOG_BASE);
 }
+
+void sp805_twdog_start(uint32_t wdog_cycles)
+{
+	sp805_wdog_start_(SP805_TWDOG_BASE, wdog_cycles);
+}
+
+void sp805_twdog_stop(void)
+{
+	sp805_wdog_stop_(SP805_TWDOG_BASE);
+}
+
+void sp805_twdog_refresh(void)
+{
+	sp805_wdog_refresh_(SP805_TWDOG_BASE);
+}