pgsql: Add missing PGDLLIMPORT markings

Add missing PGDLLIMPORT markings

All backend-side variables should be marked with PGDLLIMPORT, as per
policy introduced in 8ec569479f.  aafc05de1bf5 has forgotten
MyClientSocket, and 05c3980e7f47 LoadedSSL.

These can be spotted with a command like this one (be careful of not
switching __pg_log_level):
src/tools/mark_pgdllimport.pl $(git ls-files src/include/)

Reported-by: Peter Eisentraut
Discussion: https://postgr.es/m/ZhzkRzrkKhbeQMRm@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/768ceeeaa127a8001d60ad6a62846a8be3f35d93

Modified Files
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src/include/postmaster/postmaster.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)