syslog_inbuffer:Fixed the lock reentry issue in single core + spinlock scenario

Summary:
  When spinlock.h is enabled in a single-core scenario, spinlock reentry and exceptions may occur when spin_lock_irqsave_wo_note is used in syslog_add_intbuffer

Signed-off-by: chenrun1 <chenrun1@xiaomi.com>

Author: crafcat7

drivers/syslog/syslog_intbuffer.c

@@ -104,8 +104,6 @@ static void syslog_flush_internal(bool force, size_t buflen)
    * concurrent modification by other tasks.
    */
 
-  flags = spin_lock_irqsave_wo_note(&g_syslog_intbuffer.splock);
-
   do
     {
       buffer = circbuf_get_readptr(&g_syslog_intbuffer.circ, &size);
@@ -118,8 +116,6 @@ static void syslog_flush_internal(bool force, size_t buflen)
         }
     }
   while (size > 0 && buflen > 0);
-
-  spin_unlock_irqrestore_wo_note(&g_syslog_intbuffer.splock, flags);
 }
 
 /****************************************************************************
@@ -201,7 +197,11 @@ void syslog_add_intbuffer(FAR const char *buffer, size_t buflen)
 
 void syslog_flush_intbuffer(bool force)
 {
+  irqstate_t flags;
+
+  flags = spin_lock_irqsave_wo_note(&g_syslog_intbuffer.splock);
   syslog_flush_internal(force, sizeof(g_syslog_intbuffer.buffer));
+  spin_unlock_irqrestore_wo_note(&g_syslog_intbuffer.splock, flags);
 }
 
 #endif /* CONFIG_SYSLOG_INTBUFFER */