pgsql: Properly close files after read file failure to prevent potentia

Properly close files after read file failure to prevent potential
resource leak.  Of course, any such failure aborts pg_upgrade, but might
as well be clean about it.

Per patch from Grzegorz Ja?kiewicz.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=c767c3bd3690aa06a7965d7f9f9d80e5c15174cd

Modified Files
--------------
contrib/pg_upgrade/file.c |    3 +++
contrib/pg_upgrade/page.c |    3 +++
2 files changed, 6 insertions(+), 0 deletions(-)