pgsql: Allow vpath builds and regression tests to succeed on Mingw. Bac

Allow vpath builds and regression tests to succeed on Mingw. Backpatch to release 8.4 - earlier releases would require more changes and it's not worth the trouble.

Branch
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REL8_4_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=370a89969623647612a0d5727a143799d3b33b66

Modified Files
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src/bin/pgevent/Makefile | 2 +-
src/interfaces/ecpg/test/Makefile | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)