vbox_tmpl.c: remove useless array-is-non-NULL comparisons

* src/vbox/vbox_tmpl.c (vboxStorageVolDelete): Remove always-true
array-is-non-NULL test.  git grep 'key\[.*\];'|grep -F .h
src/datatypes.h:    char key[PATH_MAX];
(vboxStorageVolGetInfo): Likewise.
(vboxStorageVolGetXMLDesc): Likewise.
(vboxStorageVolGetPath): Likewise.
(vboxDomainDefineXML): Likewise. (but now with "mac[]")

src/vbox/vbox_tmpl.c

@@ -4084,9 +4084,7 @@ static virDomainPtr vboxDomainDefineXML(virConnectPtr conn, const char *xml) {
                 }
 
                 VBOX_UTF8_TO_UTF16(macaddrvbox, &MACAddress);
-                if (def->nets[i]->mac) {
-                    adapter->vtbl->SetMACAddress(adapter, MACAddress);
-                }
+                adapter->vtbl->SetMACAddress(adapter, MACAddress);
                 VBOX_UTF16_FREE(MACAddress);
             }
         }
@@ -6645,9 +6643,6 @@ static int vboxStorageVolDelete(virStorageVolPtr vol,
     int i = 0;
     int j = 0;
 
-    if (!vol->key)
-        return ret;
-
     vboxUtf8toIID(vol->conn, vol->key, &hddIID);
     if (!hddIID)
         return ret;
@@ -6774,8 +6769,7 @@ static int vboxStorageVolGetInfo(virStorageVolPtr vol, virStorageVolInfoPtr info
     vboxIID   *hddIID    = NULL;
     nsresult rc;
 
-    if (   !vol->key
-        || !info)
+    if (!info)
         return ret;
 
     vboxUtf8toIID(vol->conn, vol->key, &hddIID);
@@ -6824,9 +6818,6 @@ static char *vboxStorageVolGetXMLDesc(virStorageVolPtr vol, unsigned int flags A
     int defOk = 0;
     nsresult rc;
 
-    if (!vol->key)
-        return ret;
-
     memset(&pool, 0, sizeof(pool));
     memset(&def, 0, sizeof(def));
 
@@ -6919,9 +6910,6 @@ static char *vboxStorageVolGetPath(virStorageVolPtr vol) {
     vboxIID   *hddIID    = NULL;
     nsresult rc;
 
-    if (!vol->key)
-        return ret;
-
     vboxUtf8toIID(vol->conn, vol->key, &hddIID);
     if (!hddIID)
         return ret;