security: Adding delete methods in KeyChain

Change-Id: I8e3bbbf6e911b43189c510c56118d291f8932df4
diff --git a/src/security/sec-tpm-file.hpp b/src/security/sec-tpm-file.hpp
index 8ef5586..d0a68b8 100644
--- a/src/security/sec-tpm-file.hpp
+++ b/src/security/sec-tpm-file.hpp
@@ -39,6 +39,13 @@
   generateKeyPairInTpm(const Name & keyName, KeyType keyType, int keySize);
 
   /**
+   * Delete a key pair of asymmetric keys.
+   * @param keyName The name of the key pair.
+   */
+  virtual void
+  deleteKeyPairInTpm(const Name &keyName);
+
+  /**
    * Get the public key
    * @param keyName The name of public key.
    * @return The public key.