Skipping tests in evp_test leaks memory

When configured with "no-mdc2 enable-crypto-mdebug" the evp_test
will leak memory due to skipped tests, and error out.

Also fix a skip condition

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1968)