pgsql: Minor fixes to pg_combinebackup and its documentation.

Minor fixes to pg_combinebackup and its documentation.

The --tablespace-mapping option was specified with required_argument
rather than no_argument, which is wrong. Since the actual argument
string passed to getopt_long() included "T:", the single-character
form of the option still worked, but the long form did not. Repair.

The call to getopt_long() erroneously included "P", which doesn't
correspond to any supported option. Remove.

The help message used "do not" in one place and "don't" in another.
Standardize on "do not".

The documentation erroneously stated that the tablespace mappings
would be applied relative to the pathnames in the first backup
specified on the command line, rather than the final one. Fix.

Thanks to Tomas Vondra and Daniel Gustafsson for alerting me to
these mistakes.

Discussion: http://postgr.es/m/CA+TgmoYFznwwaZhHSF1Ze7JeyBv-1yOoSrucKMw37WpF=7RP8g@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1713e3d6cd393fcc1d4873e75c7fa1f6c7023d75

Modified Files
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doc/src/sgml/ref/pg_combinebackup.sgml      | 2 +-
src/bin/pg_combinebackup/pg_combinebackup.c | 6 +++---
2 files changed, 4 insertions(+), 4 deletions(-)