tzc400: add support for interrupts

A new function tzc400_it_handler() is created to manage TZC400
interrupts. The required helpers to read and clear interrupts are added
as well.
In case DEBUG is enabled, more information about the faulty access
(address, NSAID, type of access) is displayed.

Change-Id: Ie9ab1c199a8f12b2c9472d7120efbdf35711284a
Signed-off-by: Yann Gautier <yann.gautier@st.com>
diff --git a/include/drivers/arm/tzc400.h b/include/drivers/arm/tzc400.h
index aacd5df..5f8a48f 100644
--- a/include/drivers/arm/tzc400.h
+++ b/include/drivers/arm/tzc400.h
@@ -90,6 +90,8 @@
 #define TZC_400_REGION_SIZE			U(0x20)
 #define TZC_400_ACTION_OFF			U(0x4)
 
+#define FILTER_OFFSET				U(0x10)
+
 #ifndef __ASSEMBLER__
 
 #include <cdefs.h>
@@ -110,6 +112,7 @@
 void tzc400_set_action(unsigned int action);
 void tzc400_enable_filters(void);
 void tzc400_disable_filters(void);
+int tzc400_it_handler(void);
 
 static inline void tzc_init(uintptr_t base)
 {