pgAdmin III commit: Ensure png2c doesn't barf if processing a file with

Ensure png2c doesn't barf if processing a file with no path specified.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin3.git;a=commitdiff;h=84277d9cf2a7dd06c2d4e52d1bb6474b3c341385

Modified Files
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xtra/png2c/png2c.c |    2 ++
1 files changed, 2 insertions(+), 0 deletions(-)