button-handler: Add ID button actions

Creates a signal handler for the 'Released' signal.

The handler will toggle the 'Asserted' property in the
LED group defined by the configure file.  The default
group is 'enclosure_identify'.  The effect of this is
the LEDs in the group will toggle on or off on each
button press.

Tested: Used the 'simPress' method on the ID button object.

Change-Id: I9f68a8b3fae02efc7f6cfb6dbcf8a45cce7f2d9c
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/inc/button_handler.hpp b/inc/button_handler.hpp
index 0964aad..7340c2f 100644
--- a/inc/button_handler.hpp
+++ b/inc/button_handler.hpp
@@ -58,6 +58,15 @@
     void longPowerPressed(sdbusplus::message::message& msg);
 
     /**
+     * @brief The handler for an ID button press
+     *
+     * Toggles the ID LED group
+     *
+     * @param[in] msg - sdbusplus message from signal
+     */
+    void idPressed(sdbusplus::message::message& msg);
+
+    /**
      * @brief The handler for a reset button press
      *
      * Reboots the host if it is powered on.
@@ -101,6 +110,11 @@
     std::unique_ptr<sdbusplus::bus::match_t> powerButtonLongPressReleased;
 
     /**
+     * @brief Matches on the ID button released signal
+     */
+    std::unique_ptr<sdbusplus::bus::match_t> idButtonReleased;
+
+    /**
      * @brief Matches on the reset button released signal
      */
     std::unique_ptr<sdbusplus::bus::match_t> resetButtonReleased;