log: correct timestamp formatting to unsigned integer type

Closes https://github.com/espressif/esp-idf/issues/6226

Closes IDFGH-4393

components/log/include/esp_log.h

@@ -274,7 +274,7 @@ void esp_log_writev(esp_log_level_t level, const char* tag, const char* format,
 #define LOG_RESET_COLOR
 #endif //CONFIG_LOG_COLORS
 
-#define LOG_FORMAT(letter, format)  LOG_COLOR_ ## letter #letter " (%d) %s: " format LOG_RESET_COLOR "\n"
+#define LOG_FORMAT(letter, format)  LOG_COLOR_ ## letter #letter " (%u) %s: " format LOG_RESET_COLOR "\n"
 #define LOG_SYSTEM_TIME_FORMAT(letter, format)  LOG_COLOR_ ## letter #letter " (%s) %s: " format LOG_RESET_COLOR "\n"
 
 /** @endcond */