pgsql: Fix some comments in ./configure and meson setup files

Fix some comments in ./configure and meson setup files

The comments referring to SSL_CTX_set_cert_cb() in ./configure and
./configure.ac were inconsistent, as `autoreconf -i` would show. While
on it, fix a typo on a comment related to the same check in
meson.build.

Issue introduced in 8e278b6, that removed support for OpenSSL 1.0.1.
Per offlist report from Thomas Munro.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/da98d005cdbcd45af563d0c4ac86d0e9772cd15f

Modified Files
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configure | 2 +-
configure.ac | 3 +--
meson.build | 2 +-
3 files changed, 3 insertions(+), 4 deletions(-)