pgsql: Use OpenSSL EVP API for symmetric encryption in pgcrypto.

Use OpenSSL EVP API for symmetric encryption in pgcrypto.

The old "low-level" API is deprecated, and doesn't support hardware
acceleration. And this makes the code simpler, too.

Discussion: <561274F1.1030000@iki.fi>

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/5ff4a67f63fd6d3eb01ff9707d4674ed54a89f3b

Modified Files
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contrib/pgcrypto/openssl.c | 554 +++++++++++++++------------------------------
1 file changed, 178 insertions(+), 376 deletions(-)