pgsql: Remove remaining traces of Rand_OpenSSL() from the tree

Remove remaining traces of Rand_OpenSSL() from the tree

fe0a0b5 has removed the last use of this routine from pgcrypto, leading
to a useless symbol definition and an extra configure check.

Author: Michael Paquier
Reviewed-by: Daniel Gustafsson, Tom Lane
Discussion: https://postgr.es/m/20190626142544.GN1714@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/322c5bfdc3d76f6463768ecd8fced30c881b8be5

Modified Files
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configure                  | 2 +-
configure.in               | 2 +-
src/include/pg_config.h.in | 3 ---
3 files changed, 2 insertions(+), 5 deletions(-)