dccp: clean up unused DCCP_STATE_MASK definition

Remove unused DCCP_STATE_MASK macro.

Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Acked-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/dccp.h b/include/linux/dccp.h
index 010e2d8..d638e85 100644
--- a/include/linux/dccp.h
+++ b/include/linux/dccp.h
@@ -279,8 +279,6 @@
 	DCCP_MAX_STATES
 };
 
-#define DCCP_STATE_MASK 0x1f
-
 enum {
 	DCCPF_OPEN	      = TCPF_ESTABLISHED,
 	DCCPF_REQUESTING      = TCPF_SYN_SENT,