[CIFS] Ensure that cifs multiplex ids do not collide.

Signed-off-by: Steve French (sfrench@us.ibm.com)
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index d3773e5..e8287f7 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -147,6 +147,7 @@
 	/* (returned on Negotiate */
 	int capabilities; /* allow selective disabling of caps by smb sess */
 	__u16 timeZone;
+	__u16 CurrentMid;         /* multiplex id - rotating counter */
 	char cryptKey[CIFS_CRYPTO_KEY_SIZE];
 	char workstation_RFC1001_name[16]; /* 16th byte is always zero */
 	__u32 sequence_number; /* needed for CIFS PDU signature */