pgsql: Fix memory leaks in pg_combinebackup/reconstruct.c.

Fix memory leaks in pg_combinebackup/reconstruct.c.

One code path forgot to free the separately-malloc'd filename
part of a struct rfile. Another place freed the filename but
forgot the struct rfile itself. These seem worth fixing because
with a large backup we could be dealing with many files.

Coverity found the bug in make_rfile(). I found the other one
by manual inspection.

Branch
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REL_18_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/e2072b47b9abc7d298d242217919d3d0d9415fca

Modified Files
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src/bin/pg_combinebackup/reconstruct.c | 2 ++
1 file changed, 2 insertions(+)