*: use array_size() helper macro

Use the array_size() helper macro.  Replaces several instances of local
macros with the same definition.

Reviewed-by: Scott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/zebra/main.c b/zebra/main.c
index 5b5265f..50ac224 100644
--- a/zebra/main.c
+++ b/zebra/main.c
@@ -104,7 +104,7 @@
   .vty_group = VTY_GROUP,
 #endif
   .caps_p = _caps_p,
-  .cap_num_p = sizeof(_caps_p)/sizeof(_caps_p[0]),
+  .cap_num_p = array_size(_caps_p),
   .cap_num_i = 0
 };
 
@@ -313,7 +313,7 @@
   zprivs_init (&zserv_privs);
 
   /* Vty related initialize. */
-  signal_init (zebrad.master, Q_SIGC(zebra_signals), zebra_signals);
+  signal_init (zebrad.master, array_size(zebra_signals), zebra_signals);
   cmd_init (1);
   vty_init (zebrad.master);
   memory_init ();