Merge pull request #9151 from ZetaR60/RIOT_isr_debug

core/debug: fix debug.h use within ISRs

core/include/debug.h

@@ -52,7 +52,7 @@ extern "C" {
 #include "cpu_conf.h"
 #define DEBUG_PRINT(...) \
     do { \
-        if ((sched_active_thread == NULL) || (sched_active_thread->stack_size > THREAD_EXTRA_STACKSIZE_PRINTF)) { \
+        if ((sched_active_thread == NULL) || (sched_active_thread->stack_size >= THREAD_EXTRA_STACKSIZE_PRINTF)) { \
             printf(__VA_ARGS__); \
         } \
         else { \