PEL: Remove userHeader::getValue

getValue function is now being used to get field values for all the
different sections. Therefore, it makes sense to
remove the older implementation of this function from userHeader class.

Change-Id: I041b8c5e0548e9f7ee354f21d2e248ed946df5ec
Signed-off-by: Aatir <aatrapps@gmail.com>
diff --git a/extensions/openpower-pels/user_header.hpp b/extensions/openpower-pels/user_header.hpp
index 6692dd3..14407dc 100644
--- a/extensions/openpower-pels/user_header.hpp
+++ b/extensions/openpower-pels/user_header.hpp
@@ -168,20 +168,10 @@
 
     /**
      * @brief Get section in JSON.
-     * @return std::optional<std::string> - If a section comes with a JSON
-     * repressentation, this would return the string for it.
+     * @return std::optional<std::string> -User header section's JSON
      */
     std::optional<std::string> getJSON() const override;
 
-    /**
-     * @brief Helper function to get values from lookup tables.
-     * @return std::string - the value
-     * @param[in] uint8_t - field to get value for
-     * @param[in] PELValues - lookup table
-     */
-    std::string getValue(const uint8_t field,
-                         const pel_values::PELValues& values) const;
-
   private:
     /**
      * @brief Fills in the object from the stream data