Create Open firmware pseudo driver.

Change ofnet.c to disknet.c and remove almost all ieee1275 specific code.
Create grub_net_malloc to handle iee1275 memory issues in a temporary solution.

net/drivers/ieee1275/ofdriver.c

@@ -0,0 +1,74 @@
+#include <grub/net/netbuff.h>
+#include <grub/ieee1275/ofnet.h>
+#include <grub/ieee1275/ieee1275.h>
+#include <grub/net.h>
+
+static
+grub_err_t card_open (struct grub_net_card *dev)
+{
+
+  struct grub_ofnetcard_data *data = dev->data;
+  return  grub_ieee1275_open (data->path,&(data->handle)); 
+}
+
+static
+grub_err_t card_close (struct grub_net_card *dev)
+{
+
+  struct grub_ofnetcard_data *data = dev->data;
+  
+  if (data->handle)
+    grub_ieee1275_close (data->handle);
+  return GRUB_ERR_NONE;
+}
+
+static
+grub_err_t send_card_buffer (struct grub_net_card *dev, struct grub_net_buff *pack)
+{
+  
+  int actual;
+  struct grub_ofnetcard_data *data = dev->data;
+  
+  return grub_ieee1275_write (data->handle,pack->data,pack->tail - pack->data,&actual);
+}
+
+static
+grub_err_t get_card_packet (struct grub_net_card *dev, struct grub_net_buff *pack)
+{
+
+  int actual, rc;
+  struct grub_ofnetcard_data *data = dev->data;
+  grub_netbuff_clear(pack); 
+
+  do
+  {
+    rc = grub_ieee1275_read (data->handle,pack->data,1500,&actual);
+
+  }while (actual <= 0 || rc < 0);
+  grub_netbuff_put (pack, actual);
+
+  return GRUB_ERR_NONE; 
+}
+
+static struct grub_net_card_driver ofdriver = 
+{
+  .name = "ofnet",
+  .init = card_open,
+  .fini = card_close,  
+  .send = send_card_buffer, 
+  .recv = get_card_packet 
+
+};
+
+void ofdriver_ini(void)
+{
+  grub_net_card_driver_register (&ofdriver);
+}
+
+void ofdriver_fini(void)
+{
+  grub_net_card_driver_unregister (&ofdriver);
+}
+
+
+