LPC55xx: correct initial EXC_RETURN for v8-M NS.

Author: flit

source/rtos2/RTX/Source/rtx_core_cm.h

@@ -89,6 +89,11 @@ __STATIC_INLINE uint32_t xPSR_InitVal (bool_t privileged, bool_t thumb) {
 /// Stack Frame Initialization Value (EXC_RETURN[7..0])
 #if (DOMAIN_NS == 1)
 #define STACK_FRAME_INIT_VAL    0xBCU
+// --- Begin DAPLink change
+// - Change EXC_RETURN.ES and .S to 0 (NS)
+#elif (defined(__ARM_ARCH_8M_MAIN__) && (__ARM_ARCH_8M_MAIN__ != 0))
+#define STACK_FRAME_INIT_VAL    0xBCU
+// --- End DAPLink change
 #else
 #define STACK_FRAME_INIT_VAL    0xFDU
 #endif