Fix compile warnings for const correctness

Commit 6e37b1a3a25004d3df5867de49fff6b3fc9c4f04 modifies several net calls
to take a (const char *) parameter instead of (char *), but in some cases
the modified functions call other functions taking (char *).  The end result
is warnings about discarding the const qualifier.

This patch fixes these other function signatures.

Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

drivers/net/at91_emac.c

@@ -162,7 +162,7 @@ int  at91emac_write(at91_emac_t *at91mac, unsigned char addr,
 
 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
 
-at91_emac_t *get_emacbase_by_name(char *devname)
+at91_emac_t *get_emacbase_by_name(const char *devname)
 {
 	struct eth_device *netdev;
 

drivers/net/eepro100.c

@@ -321,7 +321,8 @@ static int set_phyreg (struct eth_device *dev, unsigned char addr,
 /* Check if given phyaddr is valid, i.e. there is a PHY connected.
  * Do this by checking model value field from ID2 register.
  */
-static struct eth_device* verify_phyaddr (char *devname, unsigned char addr)
+static struct eth_device* verify_phyaddr (const char *devname,
+						unsigned char addr)
 {
 	struct eth_device *dev;
 	unsigned short value;

drivers/net/phy/miiphybb.c

@@ -143,7 +143,7 @@ void bb_miiphy_init(void)
 	}
 }
 
-static inline struct bb_miiphy_bus *bb_miiphy_getbus(char *devname)
+static inline struct bb_miiphy_bus *bb_miiphy_getbus(const char *devname)
 {
 #ifdef CONFIG_BITBANGMII_MULTI
 	int i;
@@ -246,7 +246,7 @@ static void miiphy_pre(struct bb_miiphy_bus *bus, char read,
  * Returns:
  *   0 on success
  */
-int bb_miiphy_read(char *devname, unsigned char addr,
+int bb_miiphy_read(const char *devname, unsigned char addr,
 		   unsigned char reg, unsigned short *value)
 {
 	short rdreg; /* register working value */
@@ -327,7 +327,7 @@ int bb_miiphy_read(char *devname, unsigned char addr,
  * Returns:
  *   0 on success
  */
-int bb_miiphy_write (char *devname, unsigned char addr,
+int bb_miiphy_write (const char *devname, unsigned char addr,
 		     unsigned char reg, unsigned short value)
 {
 	struct bb_miiphy_bus *bus;

include/net.h

@@ -117,7 +117,7 @@ extern void eth_try_another(int first_restart);	/* Change the device */
 extern void eth_set_current(void);		/* set nterface to ethcur var */
 #endif
 extern struct eth_device *eth_get_dev(void);	/* get the current device MAC */
-extern struct eth_device *eth_get_dev_by_name(char *devname); /* get device */
+extern struct eth_device *eth_get_dev_by_name(const char *devname);
 extern struct eth_device *eth_get_dev_by_index(int index); /* get dev @ index */
 extern int eth_get_dev_index (void);		/* get the device index */
 extern void eth_parse_enetaddr(const char *addr, uchar *enetaddr);

net/eth.c

@@ -102,7 +102,7 @@ struct eth_device *eth_get_dev(void)
 	return eth_current;
 }
 
-struct eth_device *eth_get_dev_by_name(char *devname)
+struct eth_device *eth_get_dev_by_name(const char *devname)
 {
 	struct eth_device *dev, *target_dev;