net: Remove variables hooks when interface is unregisted

The grub_net_network_level_interface_unregister(), previously
implemented in a header, did not remove the variables hooks that
were registered in grub_net_network_level_interface_register().
Fix this by implementing the same logic used to register the
variables and move the function into the grub-core/net/net.c.

Signed-off-by: B Horn <b@horn.uk>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

grub-core/net/net.c

@@ -984,6 +984,38 @@ grub_net_network_level_interface_register (struct grub_net_network_level_interfa
   grub_net_network_level_interfaces = inter;
 }
 
+void
+grub_net_network_level_interface_unregister (struct grub_net_network_level_interface *inter)
+{
+  char *name;
+
+  {
+    char buf[GRUB_NET_MAX_STR_HWADDR_LEN];
+
+    grub_net_hwaddr_to_str (&inter->hwaddress, buf);
+    name = grub_xasprintf ("net_%s_mac", inter->name);
+    if (name != NULL)
+      grub_register_variable_hook (name, NULL, NULL);
+    grub_free (name);
+  }
+
+  {
+    char buf[GRUB_NET_MAX_STR_ADDR_LEN];
+
+    grub_net_addr_to_str (&inter->address, buf);
+    name = grub_xasprintf ("net_%s_ip", inter->name);
+    if (name != NULL)
+      grub_register_variable_hook (name, NULL, NULL);
+    grub_free (name);
+  }
+
+  inter->card->num_ifaces--;
+  *inter->prev = inter->next;
+  if (inter->next)
+    inter->next->prev = inter->prev;
+  inter->next = 0;
+  inter->prev = 0;
+}
 
 grub_err_t
 grub_net_add_ipv4_local (struct grub_net_network_level_interface *inter,

include/grub/net.h

@@ -540,16 +540,7 @@ void grub_bootp_fini (void);
 void grub_dns_init (void);
 void grub_dns_fini (void);
 
-static inline void
+void grub_net_network_level_interface_unregister (struct grub_net_network_level_interface *inter);
-grub_net_network_level_interface_unregister (struct grub_net_network_level_interface *inter)
-{
-  inter->card->num_ifaces--;
-  *inter->prev = inter->next;
-  if (inter->next)
-    inter->next->prev = inter->prev;
-  inter->next = 0;
-  inter->prev = 0;
-}
 
 void
 grub_net_tcp_retransmit (void);