pgsql: Simplify logic to sync target directory at the end of pg_rewind

Simplify logic to sync target directory at the end of pg_rewind

The previous sync logic relied on looking for and then launching
externally initdb -S, which is a simple wrapper on top of fsync_pgdata.
There is nothing preventing pg_rewind to directly call this routine, so
remove the dependency to initdb and just call it directly.

Author: Michael Paquier
Reviewed-by: Heikki Linnakangas
Discussion: https://postgr.es/m/20180325122607.GB3707@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9a4059d4ff1100e10d2aaadb136a04a407351249

Modified Files
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src/bin/pg_rewind/pg_rewind.c | 44 +++++--------------------------------------
1 file changed, 5 insertions(+), 39 deletions(-)