pgsql: Use RAND_poll() for seeding randomness after fork().

Use RAND_poll() for seeding randomness after fork().

OpenSSL deprecated RAND_cleanup(), and OpenSSL 1.1.0 made it into a
no-op.  Replace it with RAND_poll(), per an OpenSSL community
recommendation.  While this has no user-visible consequences under
OpenSSL defaults, it might help under non-default settings.

Daniel Gustafsson, reviewed by David Steele and Michael Paquier.

Discussion: https://postgr.es/m/9B038FA5-23E8-40D0-B932-D515E1D8F66A@yesql.se

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ce4939ff70890fa658a4095b9fe457f8432b2575

Modified Files
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src/backend/postmaster/fork_process.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)