pgsql: Be more wary of unwanted whitespace in pgstat_reset_remove_files

Be more wary of unwanted whitespace in pgstat_reset_remove_files().

sscanf isn't the easiest thing to use for exact pattern checks ...
also, don't use strncmp where strcmp will do.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/20fe87075349a205d5b6a2f4b97c2bad4e8a961c

Modified Files
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src/backend/postmaster/pgstat.c |   30 ++++++++++++++----------------
1 file changed, 14 insertions(+), 16 deletions(-)