lib: Add new if_link_params structure

This new structure is the basis to get new link parameters for
Traffic Engineering from Zebra/interface layer to OSPFD and ISISD
for the support of Traffic Engineering

* lib/if.[c,h]: link parameters struture and get/set functions
* lib/command.[c,h]: creation of a new link-node
* lib/zclient.[c,h]: modification to the ZBUS message to convey the
  link parameters structure
* lib/zebra.h: New ZBUS message
* lib/memtypes.c: Add new memory type for Traffic Engineering support

Signed-off-by: Olivier Dugeon <olivier.dugeon@orange.com>
diff --git a/lib/command.c b/lib/command.c
index fa2ef11..ab46fc4 100644
--- a/lib/command.c
+++ b/lib/command.c
@@ -2632,8 +2632,12 @@
     case KEYCHAIN_KEY_NODE:
       ret = KEYCHAIN_NODE;
       break;
+    case LINK_PARAMS_NODE:
+      ret = INTERFACE_NODE;
+      break;
     default:
       ret = CONFIG_NODE;
+      break;
     }
 
   return ret;
@@ -3003,6 +3007,9 @@
     case KEYCHAIN_KEY_NODE:
       vty->node = KEYCHAIN_NODE;
       break;
+    case LINK_PARAMS_NODE:
+      vty->node = INTERFACE_NODE;
+      break;
     default:
       break;
     }
@@ -3052,6 +3059,7 @@
     case MASC_NODE:
     case PIM_NODE:
     case VTY_NODE:
+    case LINK_PARAMS_NODE:
       vty_config_unlock (vty);
       vty->node = ENABLE_NODE;
       break;