Tobias Kortkamp d82f96fa68 databases/pgagent: Unbreak build with PostgreSQL 11+ ...

CMake Error at cmake/FindPG.cmake:74 (LIST):
  LIST index: 2 out of range (-2, 1)

http://package18.nyi.freebsd.org/data/120amd64-default-PR239514/2019-07-29_20h41m52s/logs/pgagent-3.4.0_4.log

PR:		239514

2019-08-03 09:20:32 +00:00

..

patch-cmake_FindPG.cmake

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patch-CMakeLists.txt

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