Zelda uCode (SMS): fix a bug where we would receive more sync mails that expected.

Actually the sync mail sequences contain 3 mails, not 2.
That's what happens when you don't look at the uCode enough...

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@3824 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Plugins/Plugin_DSP_HLE/Src/UCodes/UCode_Zelda.h

@@ -242,6 +242,9 @@ private:
 	u32 m_MaxVoice;
 	u32 m_SyncFlags[16];
 
+	// Used by SMS version
+	u32 m_NumSyncMail;
+
 	u32 m_NumVoices;
 
 	bool m_bSyncCmdPending;