afs: Get rid of afs_call::reply[]

Replace the afs_call::reply[] array with a bunch of typed members so that
the compiler can use type-checking on them.  It's also easier for the eye
to see what's going on.

Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/fs/afs/vl_probe.c b/fs/afs/vl_probe.c
index b05e0de..beb9915 100644
--- a/fs/afs/vl_probe.c
+++ b/fs/afs/vl_probe.c
@@ -33,8 +33,8 @@ static bool afs_vl_probe_done(struct afs_vlserver *server)
 void afs_vlserver_probe_result(struct afs_call *call)
 {
 	struct afs_addr_list *alist = call->alist;
-	struct afs_vlserver *server = call->reply[0];
-	unsigned int server_index = (long)call->reply[1];
+	struct afs_vlserver *server = call->vlserver;
+	unsigned int server_index = call->server_index;
 	unsigned int index = call->addr_ix;
 	unsigned int rtt = UINT_MAX;
 	bool have_result = false;