SSB: Fix nvram_get on BCM47xx platform

The nvram_get function was never in the mainline kernel, it only existed in
an external OpenWrt patch. Use nvram_getenv function, which is in mainline
and use an include instead of an extra function declaration.  et0macaddr
contains the mac address in text from like 00:11:22:33:44:55. We have to
parse it before adding it into macaddr.

nvram_parse_macaddr will be merged into asm/mach-bcm47xx/nvram.h through
the MIPS git tree and will be available soon. It will not build now without
nvram_parse_macaddr, but it hasn't before either.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: mb@bu3sch.de
Cc: netdev@vger.kernel.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Michael Buesch <mb@bu3sch.de>
Patchwork: https://patchwork.linux-mips.org/patch/1849/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

include/linux/ssb/ssb_driver_gige.h

@@ -96,16 +96,21 @@ static inline bool ssb_gige_must_flush_posted_writes(struct pci_dev *pdev)
 	return 0;
 }
 
-extern char * nvram_get(const char *name);
+#ifdef CONFIG_BCM47XX
+#include <asm/mach-bcm47xx/nvram.h>
 /* Get the device MAC address */
 static inline void ssb_gige_get_macaddr(struct pci_dev *pdev, u8 *macaddr)
 {
-#ifdef CONFIG_BCM47XX
-	char *res = nvram_get("et0macaddr");
-	if (res)
-		memcpy(macaddr, res, 6);
-#endif
+	char buf[20];
+	if (nvram_getenv("et0macaddr", buf, sizeof(buf)) < 0)
+		return;
+	nvram_parse_macaddr(buf, macaddr);
 }
+#else
+static inline void ssb_gige_get_macaddr(struct pci_dev *pdev, u8 *macaddr)
+{
+}
+#endif
 
 extern int ssb_gige_pcibios_plat_dev_init(struct ssb_device *sdev,
 					  struct pci_dev *pdev);