[SPARC]: Implement fb_is_primary_device().

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/asm-sparc64/fb.h b/include/asm-sparc64/fb.h
index d6cd3a1..389012e 100644
--- a/include/asm-sparc64/fb.h
+++ b/include/asm-sparc64/fb.h
@@ -3,6 +3,7 @@
 #include <linux/fb.h>
 #include <linux/fs.h>
 #include <asm/page.h>
+#include <asm/prom.h>
 
 static inline void fb_pgprotect(struct file *file, struct vm_area_struct *vma,
 				unsigned long off)
@@ -12,6 +13,14 @@
 
 static inline int fb_is_primary_device(struct fb_info *info)
 {
+	struct device *dev = info->device;
+	struct device_node *node;
+
+	node = dev->archdata.prom_node;
+	if (node &&
+	    node == of_console_device)
+		return 1;
+
 	return 0;
 }