net/smc: use DECLARE_BITMAP for rtokens_used_mask

Link group field tokens_used_mask is a bitmap. Use macro
DECLARE_BITMAP for its definition.
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/smc/smc_core.h

@@ -192,8 +192,7 @@ struct smc_link_group {
 			struct smc_rtoken	rtokens[SMC_RMBS_PER_LGR_MAX]
 						[SMC_LINKS_PER_LGR_MAX];
 						/* remote addr/key pairs */
-			unsigned long		rtokens_used_mask[BITS_TO_LONGS
-							(SMC_RMBS_PER_LGR_MAX)];
+			DECLARE_BITMAP(rtokens_used_mask, SMC_RMBS_PER_LGR_MAX);
 						/* used rtoken elements */
 		};
 		struct { /* SMC-D */