TEST: Fix test/recipes/15-test_rsa.t
TEST: Fix test/recipes/15-test_rsa.t

Perl strings should be compared with 'eq', not '=='.
This only generates a perl warning, so wasn't immediately noticed.

Also, remove the check of disabled 'dsa'.  That never made reak sense.

Reviewed-by: Tomas Mraz <973cc78d8b4cb00714230ba9be0225e917ab4ac6@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/13645)

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