Copter: fix init of wp_verify_byte so wp alt is always required

ArduCopter/commands_logic.pde

@@ -279,11 +279,6 @@ static void do_nav_wp()
     // this is our bitmask to verify we have met all conditions to move on
     wp_verify_byte  = 0;
 
-    // if no alt requirement in the waypoint, set the altitude achieved bit of wp_verify_byte
-    if((next_WP.options & WP_OPTION_ALT_REQUIRED) == false) {
-        wp_verify_byte |= NAV_ALTITUDE;
-    }
-
     // if not delay requirement, set the delay achieved bit of wp_verify_byte
     if( command_nav_queue.p1 == 0 ) {
         wp_verify_byte |= NAV_DELAY;