stmmac: rename mac100 as dwmac100 and fix spare coding style

This patch renames the mac100.[ch] as dwmac100.[ch]; this
looks more specific and appropriate for these chip series.
The patch also fixes some spare coding style issues.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/stmmac/stmmac_main.c b/drivers/net/stmmac/stmmac_main.c
index e6c5a3c..e79e00b 100644
--- a/drivers/net/stmmac/stmmac_main.c
+++ b/drivers/net/stmmac/stmmac_main.c
@@ -1585,7 +1585,7 @@
 	if (priv->is_gmac)
 		device = gmac_setup(ioaddr);
 	else
-		device = mac100_setup(ioaddr);
+		device = dwmac100_setup(ioaddr);
 
 	if (!device)
 		return -ENOMEM;