drivers/syslog: Ensure interrupt log doesn't interlace in normal log. Don't call syslog_putc in syslog_default_write because syslog_putc will try to empty the interrupt buffer every time.

include/nuttx/syslog/syslog.h

@@ -114,12 +114,12 @@ struct syslog_channel_s
 {
   /* I/O redirection methods */
 
-#ifdef CONFIG_SYSLOG_WRITE
-  syslog_write_t sc_write;  /* Write multiple bytes */
-#endif
   syslog_putc_t  sc_putc;   /* Normal buffered output */
   syslog_putc_t  sc_force;  /* Low-level output for interrupt handlers */
   syslog_flush_t sc_flush;  /* Flush buffered output (on crash) */
+#ifdef CONFIG_SYSLOG_WRITE
+  syslog_write_t sc_write;  /* Write multiple bytes */
+#endif
 
   /* Implementation specific logic may follow */
 };