board native_sim/posix: Provide NEVER/NSI_NEVER definitions

Some native_posix specific apps/tests use the macro NEVER
provided it also for native_sim until all have switched
to the new NSI_NEVER.

And ensure NSI_NEVER is also avaiable when building
for native_posix to ease the transition.

Signed-off-by: Alberto Escolar Piedras <alberto.escolar.piedras@nordicsemi.no>

boards/posix/native_posix/hw_models_top.h

@@ -15,6 +15,7 @@ extern "C" {
 #endif
 
 #define NEVER UINT64_MAX
+#define NSI_NEVER UINT64_MAX
 
 void hwm_one_event(void);
 void hwm_init(void);

boards/posix/native_sim/native_posix_compat.h

@@ -33,6 +33,8 @@ static ALWAYS_INLINE uint64_t hwm_get_time(void)
 	return nsi_hws_get_time();
 }
 
+#define NEVER NSI_NEVER
+
 #ifdef __cplusplus
 }
 #endif