[LOG] Make sure logHasOutput() returns true when semihosting is enabled

With semihosting there's always a log output. Without considering
it, logIsEnabled() would return false with semihosting enabled but
without additional log outputs.

Found by @shellixyz

src/main/common/log.c

@@ -137,7 +137,11 @@ static size_t logFormatPrefix(char *buf, const timeMs_t timeMs)
 
 static bool logHasOutput(void)
 {
+#if defined(SEMIHOSTING)
+    return true;
+#else
     return logPort || mspLogPort;
+#endif
 }
 
 static bool logIsEnabled(logTopic_e topic, unsigned level)