freertos: place uxTopUsedPriority into DRAM

When debugging crashes caused by flash cache access errors, OpenOCD may
request the value of uxTopUsedPriority when cache is disabled. Placing
it into IRAM to avoid an error in such case.

components/freertos/FreeRTOS-openocd.c

@@ -10,6 +10,7 @@
  */
 
 #include "FreeRTOS.h"
+#include "esp_attr.h"
 #include "sdkconfig.h"
 
 #ifdef __GNUC__
@@ -19,5 +20,5 @@
 #endif
 
 #ifdef CONFIG_ESP32_DEBUG_OCDAWARE
-const int USED uxTopUsedPriority = configMAX_PRIORITIES - 1;
-#endif
+const int USED DRAM_ATTR uxTopUsedPriority = configMAX_PRIORITIES - 1;
+#endif