pgsql: Remove duplicate InitPostmasterChild() call while starting a bgw

Remove duplicate InitPostmasterChild() call while starting a bgworker.

This is apparently harmless on Windows, but on Unix it results in an
assertion failure.  We'd not noticed because this code doesn't get
used on Unix unless you build with -DEXEC_BACKEND.  Bug was evidently
introduced by sloppy refactoring in commit 31c453165.

Thomas Munro

Discussion: <CAEepm=1VOnbVx4wsgQFvj94hu9jVt2nVabCr7QiooUSvPJXkgQ@mail.gmail.com>

Branch
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REL9_5_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/5816f21d8c7311ff5320c20a9d90c9e98649cec4

Modified Files
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src/backend/postmaster/postmaster.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)