Fix memory leak in DSA redo case.
Fix memory leak in DSA redo case.

Found by clang scan-build.

Signed-off-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Richard Levitte <levitte@openssl.org>

RT: #4184, MR: #1496

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl