pgsql: Fix ecpg test building process to not generate *.dSYM junk on Ma

Fix ecpg test building process to not generate *.dSYM junk on Macs.

The trick is to not try to build executables directly from .c files,
but to always build the intermediate .o files.  For obscure reasons,
Darwin's version of gcc will leave debug cruft behind in the first
case but not the second.  Per complaint from Robert Haas.

Branch
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REL8_4_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=d4346e15b477cffae44e1f2fbe1f3235abdb458b

Modified Files
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src/interfaces/ecpg/test/Makefile.regress |    3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)