pgsql: ecpg: Improve test building

ecpg: Improve test building

Further improve on commit c75e1436467f32a06b5ab9d594d2a390e7f4594d.
Instead of building both .o files and binaries in the same make rule,
just rely on the normal .c -> .o rule. This will ensure that
dependency tracking is used when enabled. To do this, disable the
implicit direct .c -> binary rule globally, which will also prevent
the original problem (*.dSYM junk) from reappearing elsewhere.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/69e9768e7b183d4b276d0e067a5a0000689580eb

Modified Files
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src/Makefile.global.in | 6 ++++++
src/interfaces/ecpg/test/Makefile.regress | 5 ++---
2 files changed, 8 insertions(+), 3 deletions(-)