component/openssl: add openssl stack function and clear unused variate

1. add openssl 'new' and 'free' function
	2. add clear unused variate to void warning to appear when compile
        3. add internal function 'X509_new' to take the place of 'sk_X509_NAME_new_null' function whitch is openssl stack function

components/openssl/include/internal/ssl_x509.h

@@ -16,10 +16,18 @@
 #define _SSL_X509_H_
 
 #include "ssl_types.h"
+#include "ssl_stack.h"
 
 DEFINE_STACK_OF(X509_NAME)
 
-X509* sk_X509_NAME_new_null(void);
+/*
+ * sk_X509_NAME_new_null - create a X509 certification object
+ *
+ * @param none
+ *
+ * @return X509 certification object point or NULL if failed
+ */
+X509* X509_new(void);
 
 X509* d2i_X509(X509 **cert, const unsigned char *buffer, long len);