pinhole: move gpio function to utils

The function to read a GPIO is needed elsewhere in later reviews so move
to the utility file.

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I994d4a912c0abe9cae6cb02d22bf5be09581d332
diff --git a/utils.hpp b/utils.hpp
index db7b361..0127206 100644
--- a/utils.hpp
+++ b/utils.hpp
@@ -34,7 +34,15 @@
                  const std::string& interface, const std::string& property,
                  const std::string& value);
 
+/** @brief Return the value of the input GPIO
+ *
+ * @param[in] gpioName          - The name of the GPIO to read
+ *
+ *  * @return The value of the gpio (0 or 1) or -1 on error
+ */
+int getGpioValue(const std::string& gpioName);
+
 } // namespace utils
 } // namespace manager
 } // namespace state
-} // namespace phosphor
\ No newline at end of file
+} // namespace phosphor