crypto/ui/ui_lib.c: Add OPENSSL_free to avoid memory leaks

crypto/ui/ui_lib.c: Add OPENSSL_free to avoid memory leaks

Add OPENSSL_free() if general_allocate_boolean() or general_allocate_string fails to avoid memory leaks.

Fixes: a63d5eaab2 ("Add a general user interface API.  This is designed to replace things like des_read_password and friends (backward compatibility functions using this new API are provided).  The purpose is to remove prompting functions from the DES code section as well as provide for prompting through dialog boxes in a window system and the like.")
Signed-off-by: JiashengJiang <jiasheng@purdue.edu>
Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
Reviewed-by: Paul Dale <ppzgs1@gmail.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/27218)