iwlwifi: iwl_poll_{direct_}bit cleanup

The patch merges implementation of iwl_poll_bit() and
iwl_poll_direct_bit() by letting the latter be a special case of
the former.

Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-rx.c b/drivers/net/wireless/iwlwifi/iwl-rx.c
index 6dd16c7..1938e6d 100644
--- a/drivers/net/wireless/iwlwifi/iwl-rx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-rx.c
@@ -467,10 +467,8 @@
 
 	/* stop Rx DMA */
 	iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
-	ret = iwl_poll_direct_bit(priv, FH_MEM_RSSR_RX_STATUS_REG,
-				     (1 << 24), 1000);
-	if (ret < 0)
-		IWL_ERROR("Can't stop Rx DMA.\n");
+	iwl_poll_direct_bit(priv, FH_MEM_RSSR_RX_STATUS_REG,
+			    FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE, 1000);
 
 	iwl_release_nic_access(priv);
 	spin_unlock_irqrestore(&priv->lock, flags);